Added custom blocks API with initial oraxen integration

fix empty nbt

.github/CODEOWNERS

@@ -0,0 +1 @@
+* @WillFP

.github/workflows/java-ci.yml

@@ -1,6 +1,6 @@
 name: Java CI
 
-on: [ push, pull_request ]
+on: [ push, pull_request, workflow_dispatch ]
 
 jobs:
   build:
@@ -14,11 +14,11 @@ jobs:
         id: vars
         run: echo "::set-output name=sha_short::$(git rev-parse --short HEAD)"
 
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v2
         with:
           distribution: 'temurin'
-          java-version: 17
+          java-version: 21
 
       - name: Setup build cache
         uses: actions/cache@v2.1.6

.github/workflows/master-pr.yml

@@ -0,0 +1,21 @@
+name: PR Alert for Master Branch
+on:
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  alert:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Comment PR
+        uses: actions/github-script@v5
+        with:
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          script: |
+            github.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: '⚠️ PRs should not be opened against the `master` branch directly. Please use the `develop` branch as the base for your PRs. ⚠️'
+            })

.github/workflows/publish-release.yml

@@ -12,11 +12,11 @@ jobs:
       - name: Checkout latest code
         uses: actions/checkout@v2
 
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v2
         with:
           distribution: 'temurin'
-          java-version: 17
+          java-version: 21
 
       - name: Setup build cache
         uses: actions/cache@v2.1.6

.github/workflows/test-publish.yml

@@ -14,11 +14,11 @@ jobs:
         id: vars
         run: echo "::set-output name=sha_short::$(git rev-parse --short HEAD)"
 
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v2
         with:
           distribution: 'temurin'
-          java-version: 17
+          java-version: 21
 
       - name: Setup build cache
         uses: actions/cache@v2.1.6

LICENSE.md

@@ -1,674 +1,23 @@
-                    GNU GENERAL PUBLIC LICENSE
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-not convey it at all.  For example, if you agree to terms that obligate you
-to collect a royalty for further conveying from those to whom you convey
-the Program, the only way you could satisfy both those terms and this
-License would be to refrain entirely from conveying the Program.
-
-  13. Use with the GNU Affero General Public License.
-
-  Notwithstanding any other provision of this License, you have
-permission to link or combine any covered work with a work licensed
-under version 3 of the GNU Affero General Public License into a single
-combined work, and to convey the resulting work.  The terms of this
-License will continue to apply to the part which is the covered work,
-but the special requirements of the GNU Affero General Public License,
-section 13, concerning interaction through a network will apply to the
-combination as such.
-
-  14. Revised Versions of this License.
-
-  The Free Software Foundation may publish revised and/or new versions of
-the GNU General Public License from time to time.  Such new versions will
-be similar in spirit to the present version, but may differ in detail to
-address new problems or concerns.
-
-  Each version is given a distinguishing version number.  If the
-Program specifies that a certain numbered version of the GNU General
-Public License "or any later version" applies to it, you have the
-option of following the terms and conditions either of that numbered
-version or of any later version published by the Free Software
-Foundation.  If the Program does not specify a version number of the
-GNU General Public License, you may choose any version ever published
-by the Free Software Foundation.
-
-  If the Program specifies that a proxy can decide which future
-versions of the GNU General Public License can be used, that proxy's
-public statement of acceptance of a version permanently authorizes you
-to choose that version for the Program.
-
-  Later license versions may give you additional or different
-permissions.  However, no additional obligations are imposed on any
-author or copyright holder as a result of your choosing to follow a
-later version.
-
-  15. Disclaimer of Warranty.
-
-  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
-APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
-HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
-OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
-THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
-IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
-ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
-
-  16. Limitation of Liability.
-
-  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
-WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
-THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
-GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
-USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
-DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
-PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
-EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
-SUCH DAMAGES.
-
-  17. Interpretation of Sections 15 and 16.
-
-  If the disclaimer of warranty and limitation of liability provided
-above cannot be given local legal effect according to their terms,
-reviewing courts shall apply local law that most closely approximates
-an absolute waiver of all civil liability in connection with the
-Program, unless a warranty or assumption of liability accompanies a
-copy of the Program in return for a fee.
-
-                     END OF TERMS AND CONDITIONS
-
-            How to Apply These Terms to Your New Programs
-
-  If you develop a new program, and you want it to be of the greatest
-possible use to the public, the best way to achieve this is to make it
-free software which everyone can redistribute and change under these terms.
-
-  To do so, attach the following notices to the program.  It is safest
-to attach them to the start of each source file to most effectively
-state the exclusion of warranty; and each file should have at least
-the "copyright" line and a pointer to where the full notice is found.
-
-    <one line to give the program's name and a brief idea of what it does.>
-    Copyright (C) <year>  <name of author>
-
-    This program is free software: you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation, either version 3 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-Also add information on how to contact you by electronic and paper mail.
-
-  If the program does terminal interaction, make it output a short
-notice like this when it starts in an interactive mode:
-
-    <program>  Copyright (C) <year>  <name of author>
-    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
-    This is free software, and you are welcome to redistribute it
-    under certain conditions; type `show c' for details.
-
-The hypothetical commands `show w' and `show c' should show the appropriate
-parts of the General Public License.  Of course, your program's commands
-might be different; for a GUI interface, you would use an "about box".
-
-  You should also get your employer (if you work as a programmer) or school,
-if any, to sign a "copyright disclaimer" for the program, if necessary.
-For more information on this, and how to apply and follow the GNU GPL, see
-<https://www.gnu.org/licenses/>.
-
-  The GNU General Public License does not permit incorporating your program
-into proprietary programs.  If your program is a subroutine library, you
-may consider it more useful to permit linking proprietary applications with
-the library.  If this is what you want to do, use the GNU Lesser General
-Public License instead of this License.  But first, please read
-<https://www.gnu.org/licenses/why-not-lgpl.html>.
+The MIT License (MIT)
+=====================
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated documentation
+files (the “Software”), to deal in the Software without
+restriction, including without limitation the rights to use,
+copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.

README.md

@@ -127,7 +127,7 @@ cd eco
 
 ## License
 
-eco is licensed under GNU GPL3. *Click here to read [the entire license](https://github.com/Auxilor/eco/blob/master/LICENSE.md).*
+eco is licensed under the MIT license. *Click here to read [the entire license](https://github.com/Auxilor/eco/blob/master/LICENSE.md).*
 
 <h1 align="center">
   Check out our partners!

build.gradle.kts

@@ -4,16 +4,17 @@ buildscript {
     }
 
     dependencies {
-        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:1.7.10")
+        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:1.9.21")
     }
 }
 
 plugins {
     id("java-library")
-    id("com.github.johnrengelman.shadow") version "7.1.2"
+    id("io.github.goooler.shadow") version "8.1.7"
     id("maven-publish")
     id("java")
-    kotlin("jvm") version "1.7.10"
+    kotlin("jvm") version "1.9.21"
+    kotlin("plugin.serialization") version "1.9.21"
 }
 
 dependencies {
@@ -21,28 +22,33 @@ dependencies {
     implementation(project(path = ":eco-core:core-plugin", configuration = "shadow"))
     implementation(project(":eco-core:core-proxy"))
     implementation(project(":eco-core:core-backend"))
+    implementation(project(":eco-core:core-backend-modern"))
     implementation(project(path = ":eco-core:core-nms:v1_17_R1", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_18_R1", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_18_R2", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_19_R1", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_19_R2", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_19_R3", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_20_R1", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_20_R2", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_20_R3", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_21", configuration = "reobf"))
 }
 
 allprojects {
     apply(plugin = "java")
     apply(plugin = "java-library")
     apply(plugin = "maven-publish")
-    apply(plugin = "com.github.johnrengelman.shadow")
+    apply(plugin = "io.github.goooler.shadow")
     apply(plugin = "kotlin")
+    apply(plugin = "org.jetbrains.kotlin.plugin.serialization")
 
     repositories {
         mavenCentral()
-        mavenLocal()
-        maven("https://jitpack.io")
-
-        // CustomCrafting
-        maven("https://maven.wolfyscript.com/repository/public/")
+        maven("https://repo.auxilor.io/repository/maven-public/")
+        maven("https://jitpack.io") {
+            content { includeGroupByRegex("com\\.github\\..*") }
+        }
 
         // SuperiorSkyblock2
         maven("https://repo.bg-software.com/repository/api/")
@@ -80,22 +86,34 @@ allprojects {
         // LibsDisguises
         maven("https://repo.md-5.net/content/groups/public/")
 
-        // UltraEconomy
-        maven("https://repo.techscode.com/repository/maven-releases/")
+        // PlayerPoints
+        maven("https://repo.rosewooddev.io/repository/public/")
+
+        // Denizen
+        maven("https://maven.citizensnpcs.co/repo")
+
+        // IridiumSkyblock
+        maven("https://nexus.iridiumdevelopment.net/repository/maven-releases/")
+
+        // HuskPlugins
+        maven("https://repo.william278.net/releases")
+
+        // FancyHolograms
+        maven("https://repo.fancyplugins.de/releases")
     }
 
     dependencies {
         // Kotlin
-        implementation(kotlin("stdlib", version = "1.7.10"))
-        implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.2")
+        implementation(kotlin("stdlib", version = "1.9.21"))
+        implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.7.3")
 
         // Included in spigot jar, no need to move to implementation
         compileOnly("org.jetbrains:annotations:23.0.0")
         compileOnly("com.google.guava:guava:31.1-jre")
 
         // Test
-        testImplementation("org.junit.jupiter:junit-jupiter-api:5.8.2")
-        testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.8.2")
+        testImplementation("org.junit.jupiter:junit-jupiter-api:5.9.2")
+        testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.9.2")
 
         // Adventure
         implementation("net.kyori:adventure-api:4.10.1")
@@ -105,8 +123,8 @@ allprojects {
         implementation("net.kyori:adventure-text-serializer-legacy:4.10.1")
 
         // Other
-        implementation("com.github.ben-manes.caffeine:caffeine:3.1.0")
-        implementation("org.apache.maven:maven-artifact:3.8.5")
+        implementation("com.github.ben-manes.caffeine:caffeine:3.1.5")
+        implementation("org.apache.maven:maven-artifact:3.9.0")
     }
 
     tasks.withType<JavaCompile> {
@@ -130,12 +148,48 @@ allprojects {
     }
 
     tasks {
+        withType<Jar> {
+            duplicatesStrategy = DuplicatesStrategy.WARN
+        }
+
         compileKotlin {
             kotlinOptions {
                 jvmTarget = "17"
             }
         }
 
+        compileJava {
+            dependsOn(clean)
+            options.encoding = "UTF-8"
+        }
+
+        test {
+            useJUnitPlatform()
+
+            // Show test results.
+            testLogging {
+                events("passed", "skipped", "failed")
+            }
+        }
+
+        build {
+            dependsOn(shadowJar)
+        }
+
+        withType<JavaCompile>().configureEach {
+            options.release = 17
+        }
+    }
+
+    java {
+        withSourcesJar()
+        toolchain {
+            languageVersion = JavaLanguageVersion.of(21)
+        }
+    }
+}
+
+tasks {
     shadowJar {
         relocate("org.bstats", "com.willfp.eco.libs.bstats")
         relocate("redempt.crunch", "com.willfp.eco.libs.crunch")
@@ -156,45 +210,19 @@ allprojects {
         relocate("google.protobuf", "com.willfp.eco.libs.protobuf") // Still don't know
         relocate("com.zaxxer.hikari", "com.willfp.eco.libs.hikari")
         //relocate("com.mysql", "com.willfp.eco.libs.mysql")
-            relocate("de.undercouch.bson4jackson", "com.willfp.eco.libs.bson4jackson")
-            relocate("com.fasterxml.jackson", "com.willfp.eco.libs.jackson")
         relocate("com.mongodb", "com.willfp.eco.libs.mongodb")
         relocate("org.bson", "com.willfp.eco.libs.bson")
         relocate("org.litote", "com.willfp.eco.libs.litote")
         relocate("org.reactivestreams", "com.willfp.eco.libs.reactivestreams")
         relocate("reactor.", "com.willfp.eco.libs.reactor.") // Dot in name to be safe
         relocate("com.moandjiezana.toml", "com.willfp.eco.libs.toml")
+        relocate("com.willfp.modelenginebridge", "com.willfp.eco.libs.modelenginebridge")
 
         /*
         Kotlin and caffeine are not shaded so that they can be accessed directly by eco plugins.
         Also, not relocating adventure, because it's a pain in the ass, and it doesn't *seem* to be causing loader constraint violations.
          */
     }
-
-        compileJava {
-            dependsOn(clean)
-            options.encoding = "UTF-8"
-        }
-
-        java {
-            sourceCompatibility = JavaVersion.VERSION_17
-            targetCompatibility = JavaVersion.VERSION_17
-            withSourcesJar()
-        }
-
-        test {
-            useJUnitPlatform()
-
-            // Show test results.
-            testLogging {
-                events("passed", "skipped", "failed")
-            }
-        }
-
-        build {
-            dependsOn(shadowJar)
-        }
-    }
 }
 
 group = "com.willfp"

eco-api/build.gradle.kts

@@ -3,7 +3,8 @@ dependencies {
     compileOnly("net.kyori:adventure-platform-bukkit:4.1.0")
 
     // Other
-    compileOnly("org.spigotmc:spigot-api:1.17.1-R0.1-SNAPSHOT")
+    compileOnly("org.spigotmc:spigot-api:1.20.2-R0.1-SNAPSHOT")
+    compileOnly("commons-lang:commons-lang:2.6")
     compileOnly("com.comphenix.protocol:ProtocolLib:4.6.1-SNAPSHOT")
     compileOnly("com.google.code.gson:gson:2.8.8")
 }

eco-api/src/main/java/com/willfp/eco/core/Eco.java

@@ -25,16 +25,18 @@ import com.willfp.eco.core.gui.menu.MenuType;
 import com.willfp.eco.core.gui.slot.SlotBuilder;
 import com.willfp.eco.core.gui.slot.functional.SlotProvider;
 import com.willfp.eco.core.items.TestableItem;
-import com.willfp.eco.core.math.MathContext;
 import com.willfp.eco.core.packet.Packet;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import com.willfp.eco.core.proxy.ProxyFactory;
 import com.willfp.eco.core.scheduling.Scheduler;
 import net.kyori.adventure.platform.bukkit.BukkitAudiences;
+import net.kyori.adventure.text.Component;
 import org.apache.commons.lang.Validate;
 import org.bukkit.Location;
 import org.bukkit.NamespacedKey;
 import org.bukkit.configuration.ConfigurationSection;
 import org.bukkit.entity.Entity;
+import org.bukkit.entity.LivingEntity;
 import org.bukkit.entity.Mob;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
@@ -135,6 +137,14 @@ public interface Eco {
     @NotNull
     Logger createLogger(@NotNull EcoPlugin plugin);
 
+    /**
+     * Get NOOP logger.
+     *
+     * @return The logger.
+     */
+    @NotNull
+    Logger getNOOPLogger();
+
     /**
      * Create a PAPI integration.
      *
@@ -170,7 +180,7 @@ public interface Eco {
      * @return The PluginCommandBase implementation
      */
     @NotNull
-    PluginCommandBase createPluginCommand(@NotNull CommandBase parentDelegate,
+    PluginCommandBase createPluginCommand(@NotNull PluginCommandBase parentDelegate,
                                           @NotNull EcoPlugin plugin,
                                           @NotNull String name,
                                           @NotNull String permission,
@@ -393,15 +403,6 @@ public interface Eco {
     @NotNull
     ServerProfile getServerProfile();
 
-    /**
-     * Unload a player profile from memory.
-     * <p>
-     * This will not save the profile first.
-     *
-     * @param uuid The uuid.
-     */
-    void unloadPlayerProfile(@NotNull UUID uuid);
-
     /**
      * Create dummy entity - never spawned, exists purely in code.
      *
@@ -528,10 +529,11 @@ public interface Eco {
      *
      * @param expression The expression.
      * @param context    The context.
-     * @return The value of the expression, or zero if invalid.
+     * @return The value of the expression, or null if invalid.
      */
-    double evaluate(@NotNull String expression,
-                    @NotNull MathContext context);
+    @Nullable
+    Double evaluate(@NotNull String expression,
+                    @NotNull PlaceholderContext context);
 
     /**
      * Get the menu a player currently has open.
@@ -563,6 +565,43 @@ public interface Eco {
     void sendPacket(@NotNull Player player,
                     @NotNull Packet packet);
 
+    /**
+     * Translate placeholders in a string.
+     *
+     * @param text    The text.
+     * @param context The context.
+     * @return The translated text.
+     */
+    @NotNull
+    String translatePlaceholders(@NotNull String text,
+                                 @NotNull PlaceholderContext context);
+
+    /**
+     * Get the value of a placeholder.
+     *
+     * @param plugin  The plugin that owns the placeholder.
+     * @param args    The placeholder arguments.
+     * @param context The context.
+     * @return The value, or null if invalid.
+     */
+    @Nullable
+    String getPlaceholderValue(@Nullable EcoPlugin plugin,
+                               @NotNull String args,
+                               @NotNull PlaceholderContext context);
+
+    /**
+     * Set a client-side entity display name.
+     *
+     * @param entity  The entity.
+     * @param player  The player.
+     * @param name    The display name.
+     * @param visible If the display name should be forcibly visible.
+     */
+    void setClientsideDisplayName(@NotNull LivingEntity entity,
+                                  @NotNull Player player,
+                                  @NotNull Component name,
+                                  boolean visible);
+
     /**
      * Get the instance of eco; the bridge between the api frontend and the implementation backend.
      *

eco-api/src/main/java/com/willfp/eco/core/EcoPlugin.java

@@ -1,5 +1,6 @@
 package com.willfp.eco.core;
 
+import com.google.common.collect.ImmutableList;
 import com.willfp.eco.core.command.impl.PluginCommand;
 import com.willfp.eco.core.config.base.ConfigYml;
 import com.willfp.eco.core.config.base.LangYml;
@@ -33,8 +34,11 @@ import org.bukkit.plugin.java.JavaPlugin;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.io.File;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
@@ -119,13 +123,21 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
 
     /**
      * The display module for the plugin.
+     *
+     * @deprecated Plugins can now have multiple display modules.
      */
+    @Deprecated(since = "6.72.0")
     private DisplayModule displayModule;
 
+    /**
+     * The display modules for the plugin.
+     */
+    private List<DisplayModule> displayModules = new ArrayList<>();
+
     /**
      * The logger for the plugin.
      */
-    private final Logger logger;
+    private Logger logger;
 
     /**
      * If the server is running an outdated version of the plugin.
@@ -163,6 +175,11 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      */
     private final ListMap<LifecyclePosition, Runnable> afterLoad = new ListMap<>();
 
+    /**
+     * The tasks to run on task creation.
+     */
+    private final ListMap<LifecyclePosition, Runnable> onCreateTasks = new ListMap<>();
+
     /**
      * Create a new plugin.
      * <p>
@@ -366,7 +383,6 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
     public final void onEnable() {
         super.onEnable();
 
-        this.getLogger().info("");
         this.getLogger().info("Loading " + this.getColor() + this.getName());
 
         if (this.getResourceId() != 0 && !Eco.get().getEcoPlugin().getConfigYml().getBool("no-update-checker")) {
@@ -406,7 +422,9 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
 
         this.loadedIntegrations.removeIf(pl -> pl.equalsIgnoreCase(this.getName()));
 
+        if (!this.getLoadedIntegrations().isEmpty()) {
             this.getLogger().info("Loaded integrations: " + String.join(", ", this.getLoadedIntegrations()));
+        }
 
         Prerequisite.update();
 
@@ -423,22 +441,35 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
 
         this.loadPluginCommands().forEach(PluginCommand::register);
 
-        this.getScheduler().runLater(this::afterLoad, 1);
+        // Run preliminary reload to resolve load order issues
+        this.getScheduler().runLater(() -> {
+            Logger before = this.getLogger();
+            // Temporary silence logger.
+            this.logger = Eco.get().getNOOPLogger();
+
+            this.reload(false);
+
+            this.logger = before;
+        }, 1);
+
+        this.getScheduler().runLater(this::afterLoad, 2);
 
         if (this.isSupportingExtensions()) {
             this.getExtensionLoader().loadExtensions();
 
-            if (this.getExtensionLoader().getLoadedExtensions().isEmpty()) {
-                this.getLogger().info("&cNo extensions found");
-            } else {
-                this.getLogger().info("Extensions Loaded:");
-                this.getExtensionLoader().getLoadedExtensions().forEach(extension -> this.getLogger().info("- " + extension.getName() + " v" + extension.getVersion()));
+            if (!this.getExtensionLoader().getLoadedExtensions().isEmpty()) {
+                List<String> loadedExtensions = this.getExtensionLoader().getLoadedExtensions().stream().map(
+                        extension -> extension.getName() + " v" + extension.getVersion()
+                ).toList();
+
+                this.getLogger().info(
+                        "Loaded extensions: " +
+                                String.join(", ", loadedExtensions)
+                );
             }
         }
 
         this.handleLifecycle(this.onEnable, this::handleEnable);
-
-        this.getLogger().info("");
     }
 
     /**
@@ -535,10 +566,15 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      * Default code to be executed after the server is up.
      */
     public final void afterLoad() {
-        this.displayModule = createDisplayModule();
+        DisplayModule module = createDisplayModule();
+        if (module != null) {
+            Display.registerDisplayModule(module);
+            this.displayModules.add(module);
+        }
 
-        if (this.getDisplayModule() != null) {
-            Display.registerDisplayModule(this.getDisplayModule());
+        for (DisplayModule displayModule : this.loadDisplayModules()) {
+            Display.registerDisplayModule(displayModule);
+            this.displayModules.add(displayModule);
         }
 
         if (Prerequisite.HAS_PROTOCOLLIB.isMet()) {
@@ -555,8 +591,9 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
             this.getLogger().severe("");
             this.getLogger().severe("You don't seem to be running paper!");
             this.getLogger().severe("Paper is strongly recommended for all servers,");
-            this.getLogger().severe("and some things may not function properly without it");
-            this.getLogger().severe("Download Paper from &fhttps://papermc.io");
+            this.getLogger().severe("and many features may not function properly without it");
+            this.getLogger().severe("Download Paper from https://papermc.io");
+            this.getLogger().severe("It's a drop-in replacement for Spigot, so it's easy to switch.");
             this.getLogger().severe("");
             this.getLogger().severe("----------------------------");
             this.getLogger().severe("");
@@ -597,14 +634,30 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      * Reload the plugin.
      */
     public final void reload() {
+        this.reload(true);
+    }
+
+    /**
+     * Reload the plugin.
+     *
+     * @param cancelTasks If tasks should be cancelled.
+     */
+    public final void reload(final boolean cancelTasks) {
         this.getConfigHandler().updateConfigs();
 
+        if (cancelTasks) {
             this.getScheduler().cancelAll();
+        }
+
         this.getConfigHandler().callUpdate();
         this.getConfigHandler().callUpdate(); // Call twice to fix issues
 
         this.handleLifecycle(this.onReload, this::handleReload);
 
+        if (cancelTasks) {
+            this.handleLifecycle(this.onCreateTasks, this::createTasks);
+        }
+
         for (Extension extension : this.extensionLoader.getLoadedExtensions()) {
             extension.handleReload();
         }
@@ -630,6 +683,26 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
         this.onReload.append(position, task);
     }
 
+    /**
+     * Add new task to run on createTasks.
+     *
+     * @param task The task.
+     */
+    public final void onCreateTasks(@NotNull final Runnable task) {
+        this.onCreateTasks(LifecyclePosition.END, task);
+    }
+
+    /**
+     * Add new task to run on createTasks.
+     *
+     * @param position The position to run the task.
+     * @param task     The task.
+     */
+    public final void onCreateTasks(@NotNull final LifecyclePosition position,
+                                    @NotNull final Runnable task) {
+        this.onCreateTasks.append(position, task);
+    }
+
     /**
      * Reload the plugin and return the time taken to reload.
      *
@@ -718,6 +791,15 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
 
     }
 
+    /**
+     * The plugin-specific code to create tasks.
+     * <p>
+     * Override when needed.
+     */
+    protected void createTasks() {
+
+    }
+
     /**
      * The plugin-specific code to be executed after the server is up.
      * <p>
@@ -833,14 +915,25 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      * Create the display module for the plugin.
      *
      * @return The display module, or null.
+     * @deprecated Use {@link #loadDisplayModules()} instead.
      */
     @Nullable
+    @Deprecated(since = "6.72.0")
     protected DisplayModule createDisplayModule() {
         Validate.isTrue(this.getDisplayModule() == null, "Display module exists!");
 
         return null;
     }
 
+    /**
+     * Load display modules.
+     *
+     * @return The display modules.
+     */
+    protected List<DisplayModule> loadDisplayModules() {
+        return new ArrayList<>();
+    }
+
     /**
      * Get the minimum version of eco to use the plugin.
      *
@@ -1082,7 +1175,7 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      *
      * @return The config handler.
      */
-    public ConfigHandler getConfigHandler() {
+    public @NotNull ConfigHandler getConfigHandler() {
         return this.configHandler;
     }
 
@@ -1090,12 +1183,23 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      * Get the plugin's display module.
      *
      * @return The display module.
+     * @deprecated Use {@link #getDisplayModules()} instead.
      */
     @Nullable
+    @Deprecated(since = "6.72.0", forRemoval = true)
     public DisplayModule getDisplayModule() {
         return this.displayModule;
     }
 
+    /**
+     * Get the plugin's display modules.
+     *
+     * @return The display modules.
+     */
+    public List<DisplayModule> getDisplayModules() {
+        return ImmutableList.copyOf(this.displayModules);
+    }
+
     /**
      * Get if the plugin is outdated.
      *
@@ -1146,9 +1250,24 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
         return this.getMetadataValueFactory().create(value);
     }
 
+    /**
+     * Get if all {@link com.willfp.eco.core.data.keys.PersistentDataKey}'s for this
+     * plugin should be saved locally (via data.yml.) even if eco is using a database.
+     *
+     * @return If using local storage.
+     */
+    public boolean isUsingLocalStorage() {
+        return this.configYml.isUsingLocalStorage();
+    }
+
     @Override
     @NotNull
     public final String getID() {
         return Registry.tryFitPattern(this.getName());
     }
+
+    @Override
+    public @NotNull File getFile() {
+        return super.getFile();
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/PluginLike.java

@@ -1,6 +1,8 @@
 package com.willfp.eco.core;
 
 import com.willfp.eco.core.config.updating.ConfigHandler;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
 import java.util.logging.Logger;
@@ -13,12 +15,13 @@ import java.util.logging.Logger;
  */
 public interface PluginLike {
     /**
-     * Get the data folder of the object.
+     * Get the data folder.
      * <p>
      * Returns the plugin data folder for a plugin, or the extension's parent plugin's folder
      *
      * @return The data folder.
      */
+    @NotNull
     File getDataFolder();
 
     /**
@@ -26,6 +29,7 @@ public interface PluginLike {
      *
      * @return The config handler.
      */
+    @NotNull
     ConfigHandler getConfigHandler();
 
     /**
@@ -33,5 +37,16 @@ public interface PluginLike {
      *
      * @return The logger.
      */
+    @NotNull
     Logger getLogger();
+
+    /**
+     * Get the actual file.
+     *
+     * @return The file, i.e. the jar file.
+     */
+    @Nullable
+    default File getFile() {
+        return null;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/PluginProps.java

@@ -55,7 +55,7 @@ public final class PluginProps {
     private final Map<String, String> environment = new HashMap<>();
 
     /**
-     * If the plugin uses reflective reload (via {@link com.willfp.eco.core.config.updating.ConfigUpdater}).
+     * If the plugin uses reflective reload.
      */
     private boolean usesReflectiveReload = true;
 

eco-api/src/main/java/com/willfp/eco/core/Prerequisite.java

@@ -37,11 +37,44 @@ public class Prerequisite {
             "Requires server to have ProtocolLib"
     );
 
+    /**
+     * Requires the server to be running 1.21.
+     */
+    public static final Prerequisite HAS_1_21 = new Prerequisite(
+            () -> ProxyConstants.NMS_VERSION.contains("1_21"),
+            "Requires server to be running 1.21+"
+    );
+
+    /**
+     * Requires the server to be running 1.20.5.
+     */
+    public static final Prerequisite HAS_1_20_5 = new Prerequisite(
+            () -> (ProxyConstants.NMS_VERSION.contains("1_20_") && !ProxyConstants.NMS_VERSION.contains("R"))
+                    || HAS_1_21.isMet(),
+            "Requires server to be running 1.20.5+"
+    );
+
+    /**
+     * Requires the server to be running 1.20.3.
+     */
+    public static final Prerequisite HAS_1_20_3 = new Prerequisite(
+            () -> ProxyConstants.NMS_VERSION.contains("20_R3") || HAS_1_20_5.isMet(),
+            "Requires server to be running 1.20.3+"
+    );
+
+    /**
+     * Requires the server to be running 1.20.
+     */
+    public static final Prerequisite HAS_1_20 = new Prerequisite(
+            () -> ProxyConstants.NMS_VERSION.contains("20") || HAS_1_20_3.isMet(),
+            "Requires server to be running 1.20+"
+    );
+
     /**
      * Requires the server to be running 1.19.4.
      */
     public static final Prerequisite HAS_1_19_4 = new Prerequisite(
-            () -> ProxyConstants.NMS_VERSION.contains("19_R3"),
+            () -> ProxyConstants.NMS_VERSION.contains("19_R3") || HAS_1_20.isMet(),
             "Requires server to be running 1.19.4+"
     );
 
@@ -49,7 +82,7 @@ public class Prerequisite {
      * Requires the server to be running 1.19.
      */
     public static final Prerequisite HAS_1_19 = new Prerequisite(
-            () -> ProxyConstants.NMS_VERSION.contains("19"),
+            () -> ProxyConstants.NMS_VERSION.contains("19") || HAS_1_20.isMet(),
             "Requires server to be running 1.19+"
     );
 

eco-api/src/main/java/com/willfp/eco/core/blocks/Blocks.java

@@ -0,0 +1,149 @@
+package com.willfp.eco.core.blocks;
+
+import com.willfp.eco.core.blocks.impl.EmptyTestableBlock;
+import com.willfp.eco.core.blocks.impl.MaterialTestableBlock;
+import com.willfp.eco.core.blocks.impl.UnrestrictedMaterialTestableBlock;
+import com.willfp.eco.core.blocks.provider.BlockProvider;
+import com.willfp.eco.util.NamespacedKeyUtils;
+import org.bukkit.Location;
+import org.bukkit.Material;
+import org.bukkit.NamespacedKey;
+import org.bukkit.block.Block;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Class to manage all custom and vanilla blocks.
+ */
+public final class Blocks {
+    /**
+     * All entities.
+     */
+    private static final Map<NamespacedKey, TestableBlock> REGISTRY = new ConcurrentHashMap<>();
+
+    /**
+     * All block providers.
+     */
+    private static final Map<String, BlockProvider> PROVIDERS = new ConcurrentHashMap<>();
+
+    /**
+     * The lookup handler.
+     */
+    private static final BlocksLookupHandler BLOCKS_LOOKUP_HANDLER = new BlocksLookupHandler(Blocks::doParse);
+
+    /**
+     * Register a new custom block.
+     *
+     * @param key   The key of the block.
+     * @param block The block.
+     */
+    public static void registerCustomBlock(@NotNull final NamespacedKey key,
+                                           @NotNull final TestableBlock block) {
+        REGISTRY.put(key, block);
+    }
+
+    /**
+     * Register a new block provider.
+     *
+     * @param provider The provider.
+     */
+    public static void registerBlockProvider(@NotNull final BlockProvider provider) {
+        PROVIDERS.put(provider.getNamespace(), provider);
+    }
+
+    /**
+     * Remove a block.
+     *
+     * @param key The key of the block.
+     */
+    public static void removeCustomBlock(@NotNull final NamespacedKey key) {
+        REGISTRY.remove(key);
+    }
+
+    /**
+     * This is the backbone of the eco block system.
+     * <p>
+     * You can look up a TestableBlock for any material or custom block,
+     * and it will return it.
+     * <p>
+     * If you want to get a Block instance from this, then just call
+     * {@link TestableBlock#place(Location)}.
+     *
+     * @param key The lookup string.
+     * @return The testable block, or an empty testable block if not found.
+     */
+    @NotNull
+    public static TestableBlock lookup(@NotNull final String key) {
+        return BLOCKS_LOOKUP_HANDLER.parseKey(key);
+    }
+
+    @NotNull
+    private static TestableBlock doParse(@NotNull final String[] args) {
+        if (args.length == 0) {
+            return new EmptyTestableBlock();
+        }
+
+        String[] split = args[0].toLowerCase().split(":");
+        if (split.length == 1) {
+            if (args[0].startsWith("*")) {
+                Material type = Material.getMaterial(args[0].substring(1));
+                return (type == null) ? new EmptyTestableBlock() : new UnrestrictedMaterialTestableBlock(type);
+            } else {
+                Material type = Material.getMaterial(args[0].toUpperCase());
+                return (type == null) ? new EmptyTestableBlock() : new MaterialTestableBlock(type);
+            }
+        }
+
+        NamespacedKey namespacedKey = NamespacedKeyUtils.create(split[0], split[1]);
+        TestableBlock block = REGISTRY.get(namespacedKey);
+
+        if (block != null) {
+            return block;
+        }
+
+        BlockProvider provider = PROVIDERS.get(split[0]);
+        if (provider == null) {
+            return new EmptyTestableBlock();
+        }
+
+        block = provider.provideForKey(split[1]);
+        if (block == null) {
+            return new EmptyTestableBlock();
+        }
+
+        registerCustomBlock(namespacedKey, block);
+        return block;
+    }
+
+    /**
+     * Get if block is a custom block.
+     *
+     * @param block The block to check.
+     * @return If is custom.
+     */
+    public static boolean isCustomBlock(@NotNull final Block block) {
+        for (TestableBlock testable : REGISTRY.values()) {
+            if (testable.matches(block)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Get all registered custom blocks.
+     *
+     * @return A set of all blocks.
+     */
+    public static Set<TestableBlock> getCustomBlocks() {
+        return new HashSet<>(REGISTRY.values());
+    }
+
+    private Blocks() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/blocks/BlocksLookupHandler.java

@@ -0,0 +1,48 @@
+package com.willfp.eco.core.blocks;
+
+import com.willfp.eco.core.blocks.impl.EmptyTestableBlock;
+import com.willfp.eco.core.blocks.impl.GroupedTestableBlocks;
+import com.willfp.eco.core.lookup.LookupHandler;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Collection;
+import java.util.function.Function;
+
+/**
+ * Handle block lookup strings.
+ */
+public class BlocksLookupHandler implements LookupHandler<TestableBlock> {
+    /**
+     * The parser.
+     */
+    private final Function<String[], @NotNull TestableBlock> parser;
+
+    /**
+     * Create new lookup handler.
+     *
+     * @param parser The parser.
+     */
+    public BlocksLookupHandler(@NotNull final Function<String[], @NotNull TestableBlock> parser) {
+        this.parser = parser;
+    }
+
+    @Override
+    public @NotNull TestableBlock parse(@NotNull final String[] args) {
+        return parser.apply(args);
+    }
+
+    @Override
+    public boolean validate(@NotNull final TestableBlock object) {
+        return !(object instanceof EmptyTestableBlock);
+    }
+
+    @Override
+    public @NotNull TestableBlock getFailsafe() {
+        return new EmptyTestableBlock();
+    }
+
+    @Override
+    public @NotNull TestableBlock join(@NotNull final Collection<TestableBlock> options) {
+        return new GroupedTestableBlocks(options);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/blocks/CustomBlock.java

@@ -0,0 +1,84 @@
+package com.willfp.eco.core.blocks;
+
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.NamespacedKey;
+import org.bukkit.block.Block;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Function;
+import java.util.function.Predicate;
+
+/**
+ * A custom block has 3 components.
+ *
+ * <ul>
+ *     <li>The key to identify it</li>
+ *     <li>The test to check if any block is this custom block</li>
+ *     <li>The supplier to spawn the custom {@link Block}</li>
+ * </ul>
+ */
+public class CustomBlock implements TestableBlock {
+    /**
+     * The key.
+     */
+    private final NamespacedKey key;
+
+    /**
+     * The test for block to pass.
+     */
+    private final Predicate<@NotNull Block> test;
+
+    /**
+     * The provider to spawn the block.
+     */
+    private final Function<Location, Block> provider;
+
+    /**
+     * Create a new custom block.
+     *
+     * @param key      The block key.
+     * @param test     The test.
+     * @param provider The provider to spawn the block.
+     */
+    public CustomBlock(@NotNull final NamespacedKey key,
+                       @NotNull final Predicate<@NotNull Block> test,
+                       @NotNull final Function<Location, Block> provider) {
+        this.key = key;
+        this.test = test;
+        this.provider = provider;
+    }
+
+    @Override
+    public boolean matches(@Nullable final Block other) {
+        if (other == null) {
+            return false;
+        }
+
+        return test.test(other);
+    }
+
+    @Override
+    public @NotNull Block place(@NotNull final Location location) {
+        Validate.notNull(location.getWorld());
+
+        return provider.apply(location);
+    }
+
+    /**
+     * Register the block.
+     */
+    public void register() {
+        Blocks.registerCustomBlock(this.getKey(), this);
+    }
+
+    /**
+     * Get the key.
+     *
+     * @return The key.
+     */
+    public NamespacedKey getKey() {
+        return this.key;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/blocks/TestableBlock.java

@@ -0,0 +1,31 @@
+package com.willfp.eco.core.blocks;
+
+import com.willfp.eco.core.lookup.Testable;
+import org.bukkit.Location;
+import org.bukkit.block.Block;
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * A block with a test.
+ */
+public interface TestableBlock extends Testable<Block> {
+    /**
+     * If a Block matches the test.
+     *
+     * @param other The other block.
+     * @return If the block matches.
+     */
+    @Override
+    boolean matches(@Nullable Block other);
+
+    /**
+     * Place the block.
+     *
+     * @param location The location.
+     * @return The block.
+     */
+    @NotNull
+    Block place(@NotNull Location location);
+}

eco-api/src/main/java/com/willfp/eco/core/blocks/impl/EmptyTestableBlock.java

@@ -0,0 +1,29 @@
+package com.willfp.eco.core.blocks.impl;
+
+import com.willfp.eco.core.blocks.TestableBlock;
+import org.bukkit.Location;
+import org.bukkit.block.Block;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Empty block.
+ */
+public class EmptyTestableBlock implements TestableBlock {
+    /**
+     * Create a new empty testable block.
+     */
+    public EmptyTestableBlock() {
+
+    }
+
+    @Override
+    public boolean matches(@Nullable final Block other) {
+        return false;
+    }
+
+    @Override
+    public @NotNull Block place(@NotNull final Location location) {
+        return location.getBlock();
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/blocks/impl/GroupedTestableBlocks.java

@@ -0,0 +1,60 @@
+package com.willfp.eco.core.blocks.impl;
+
+import com.willfp.eco.core.blocks.TestableBlock;
+import com.willfp.eco.util.NumberUtils;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.block.Block;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+/**
+ * A group of testable blocks.
+ */
+public class GroupedTestableBlocks implements TestableBlock {
+    /**
+     * The children.
+     */
+    private final Collection<TestableBlock> children;
+
+    /**
+     * Create a new group of testable blocks.
+     *
+     * @param children The children.
+     */
+    public GroupedTestableBlocks(@NotNull final Collection<TestableBlock> children) {
+        Validate.isTrue(!children.isEmpty(), "Group must have at least one child!");
+
+        this.children = children;
+    }
+
+    @Override
+    public boolean matches(@Nullable final Block other) {
+        for (TestableBlock child : children) {
+            if (child.matches(other)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    @Override
+    public @NotNull Block place(@NotNull final Location location) {
+        return new ArrayList<>(children)
+                .get(NumberUtils.randInt(0, children.size() - 1))
+                .place(location);
+    }
+
+    /**
+     * Get the children.
+     *
+     * @return The children.
+     */
+    public Collection<TestableBlock> getChildren() {
+        return new ArrayList<>(children);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/blocks/impl/MaterialTestableBlock.java

@@ -0,0 +1,59 @@
+package com.willfp.eco.core.blocks.impl;
+
+import com.willfp.eco.core.blocks.Blocks;
+import com.willfp.eco.core.blocks.TestableBlock;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.Material;
+import org.bukkit.block.Block;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * A testable block for vanilla materials.
+ */
+public class MaterialTestableBlock implements TestableBlock {
+    /**
+     * The block type.
+     */
+    private final Material material;
+
+    /**
+     * Create a new unrestricted material testable block.
+     *
+     * @param material The material.
+     */
+    public MaterialTestableBlock(@NotNull final Material material) {
+        this.material = material;
+    }
+
+    @Override
+    public boolean matches(@Nullable final Block block) {
+        boolean simpleMatches = block != null && block.getType() == material;
+
+        if (!simpleMatches) {
+            return false;
+        }
+
+        return !Blocks.isCustomBlock(block);
+    }
+
+    @Override
+    public @NotNull Block place(@NotNull Location location) {
+        Validate.notNull(location.getWorld());
+
+        Block block = location.getWorld().getBlockAt(location);
+        block.setType(material);
+
+        return block;
+    }
+
+    /**
+     * Get the material.
+     *
+     * @return The material.
+     */
+    public Material getMaterial() {
+        return this.material;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/blocks/impl/UnrestrictedMaterialTestableBlock.java

@@ -0,0 +1,52 @@
+package com.willfp.eco.core.blocks.impl;
+
+import com.willfp.eco.core.blocks.TestableBlock;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.Material;
+import org.bukkit.block.Block;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * A testable block for materials regardless of data.
+ */
+public class UnrestrictedMaterialTestableBlock implements TestableBlock {
+    /**
+     * The block type.
+     */
+    private final Material material;
+
+    /**
+     * Create a new unrestricted material testable block.
+     *
+     * @param material The material.
+     */
+    public UnrestrictedMaterialTestableBlock(@NotNull final Material material) {
+        this.material = material;
+    }
+
+    @Override
+    public boolean matches(@Nullable final Block other) {
+        return other != null && other.getType() == material;
+    }
+
+    @Override
+    public @NotNull Block place(@NotNull Location location) {
+        Validate.notNull(location.getWorld());
+
+        Block block = location.getWorld().getBlockAt(location);
+        block.setType(material);
+
+        return block;
+    }
+
+    /**
+     * Get the material.
+     *
+     * @return The material.
+     */
+    public Material getMaterial() {
+        return this.material;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/blocks/provider/BlockProvider.java

@@ -0,0 +1,49 @@
+package com.willfp.eco.core.blocks.provider;
+
+import com.willfp.eco.core.blocks.TestableBlock;
+import com.willfp.eco.core.registry.Registry;
+import org.apache.commons.lang.Validate;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Block providers are call-site registrations for blocks. In other words,
+ * they only register their blocks when a request is made. This is marginally
+ * slower, however it is required for certain plugins, and fixes bugs related to
+ * loading orders.
+ *
+ * @see TestableBlock
+ */
+public abstract class BlockProvider {
+    /**
+     * The namespace.
+     */
+    private final String namespace;
+
+    /**
+     * Create a new BlockProvider for a specific namespace.
+     *
+     * @param namespace The namespace.
+     */
+    protected BlockProvider(@NotNull final String namespace) {
+        this.namespace = namespace;
+    }
+
+    /**
+     * Provide a TestableBlock for a given key.
+     *
+     * @param key The block ID.
+     * @return The TestableBlock, or null if not found.
+     */
+    @Nullable
+    public abstract TestableBlock provideForKey(@NotNull String key);
+
+    /**
+     * Get the namespace.
+     *
+     * @return The namespace.
+     */
+    public String getNamespace() {
+        return this.namespace;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/config/base/ConfigYml.java

@@ -9,6 +9,11 @@ import org.jetbrains.annotations.NotNull;
  * Default plugin config.yml.
  */
 public class ConfigYml extends BaseConfig {
+    /**
+     * The use local storage key.
+     */
+    public static final String KEY_USES_LOCAL_STORAGE = "use-local-storage";
+
     /**
      * Config.yml.
      *
@@ -52,4 +57,13 @@ public class ConfigYml extends BaseConfig {
                      final boolean removeUnused) {
         super(name, plugin, removeUnused, ConfigType.YAML);
     }
+
+    /**
+     * Get if the plugin is using local storage.
+     *
+     * @return The prefix.
+     */
+    public boolean isUsingLocalStorage() {
+        return this.getBool(KEY_USES_LOCAL_STORAGE);
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/config/interfaces/Config.java

@@ -6,6 +6,7 @@ import com.willfp.eco.core.config.Configs;
 import com.willfp.eco.core.placeholder.AdditionalPlayer;
 import com.willfp.eco.core.placeholder.InjectablePlaceholder;
 import com.willfp.eco.core.placeholder.PlaceholderInjectable;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import com.willfp.eco.util.NumberUtils;
 import com.willfp.eco.util.StringUtils;
 import org.bukkit.configuration.ConfigurationSection;
@@ -14,6 +15,7 @@ import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -134,7 +136,7 @@ public interface Config extends Cloneable, PlaceholderInjectable {
      * @return The computed value, or 0 if not found or invalid.
      */
     default int getIntFromExpression(@NotNull String path) {
-        return getIntFromExpression(path, null);
+        return getIntFromExpression(path, PlaceholderContext.of(this));
     }
 
     /**
@@ -163,6 +165,18 @@ public interface Config extends Cloneable, PlaceholderInjectable {
         return Double.valueOf(getDoubleFromExpression(path, player, additionalPlayers)).intValue();
     }
 
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path    The key to fetch the value from.
+     * @param context The placeholder context.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default int getIntFromExpression(@NotNull String path,
+                                     @NotNull PlaceholderContext context) {
+        return Double.valueOf(getDoubleFromExpression(path, context)).intValue();
+    }
+
 
     /**
      * Get an integer from config.
@@ -256,6 +270,22 @@ public interface Config extends Cloneable, PlaceholderInjectable {
         return getString(path, true, option);
     }
 
+    /**
+     * Get a formatted string from config.
+     *
+     * @param path    The key to fetch the value from.
+     * @param context The placeholder context.
+     * @return The found value, or an empty string if not found.
+     */
+    @NotNull
+    default String getFormattedString(@NotNull String path,
+                                      @NotNull PlaceholderContext context) {
+        return Objects.requireNonNullElse(
+                getFormattedStringOrNull(path, context),
+                ""
+        );
+    }
+
     /**
      * Get a string from config.
      * <p>
@@ -288,7 +318,7 @@ public interface Config extends Cloneable, PlaceholderInjectable {
      * Get a formatted string from config.
      *
      * @param path The key to fetch the value from.
-     * @return The found value, or an empty string if not found.
+     * @return The found value, or null if not found.
      */
     @Nullable
     default String getFormattedStringOrNull(@NotNull String path) {
@@ -300,7 +330,7 @@ public interface Config extends Cloneable, PlaceholderInjectable {
      *
      * @param path   The key to fetch the value from.
      * @param option The format option.
-     * @return The found value, or an empty string if not found.
+     * @return The found value, or null if not found.
      */
     @Nullable
     default String getFormattedStringOrNull(@NotNull String path,
@@ -308,6 +338,25 @@ public interface Config extends Cloneable, PlaceholderInjectable {
         return getStringOrNull(path, true, option);
     }
 
+    /**
+     * Get a formatted string from config.
+     *
+     * @param path    The key to fetch the value from.
+     * @param context The placeholder context.
+     * @return The found value, or null if not found.
+     */
+    @Nullable
+    default String getFormattedStringOrNull(@NotNull String path,
+                                            @NotNull PlaceholderContext context) {
+        String nullable = getStringOrNull(path);
+
+        if (nullable == null) {
+            return null;
+        }
+
+        return StringUtils.format(nullable, context.withInjectableContext(this));
+    }
+
     /**
      * Get a string from config.
      * <p>
@@ -362,6 +411,24 @@ public interface Config extends Cloneable, PlaceholderInjectable {
         return getStrings(path, true, option);
     }
 
+    /**
+     * Get a list of strings from config.
+     * <p>
+     * Formatted.
+     *
+     * @param path    The key to fetch the value from.
+     * @param context The placeholder context.
+     * @return The found value, or a blank {@link java.util.ArrayList} if not found.
+     */
+    @NotNull
+    default List<String> getFormattedStrings(@NotNull String path,
+                                             @NotNull PlaceholderContext context) {
+        return Objects.requireNonNullElse(
+                getFormattedStringsOrNull(path, context),
+                new ArrayList<>()
+        );
+    }
+
     /**
      * Get a list of strings from config.
      * <p>
@@ -418,6 +485,30 @@ public interface Config extends Cloneable, PlaceholderInjectable {
         return getStringsOrNull(path, true, option);
     }
 
+    /**
+     * Get a list of strings from config.
+     * <p>
+     * Formatted.
+     *
+     * @param path    The key to fetch the value from.
+     * @param context The placeholder context.
+     * @return The found value, or null if not found.
+     */
+    @Nullable
+    default List<String> getFormattedStringsOrNull(@NotNull String path,
+                                                   @NotNull PlaceholderContext context) {
+        List<String> nullable = getStringsOrNull(path);
+
+        if (nullable == null) {
+            return null;
+        }
+
+        return StringUtils.formatList(
+                nullable,
+                context.withInjectableContext(this)
+        );
+    }
+
     /**
      * Get a list of strings from config.
      * <p>
@@ -463,7 +554,7 @@ public interface Config extends Cloneable, PlaceholderInjectable {
      * @return The computed value, or 0 if not found or invalid.
      */
     default double getDoubleFromExpression(@NotNull String path) {
-        return getDoubleFromExpression(path, null);
+        return getDoubleFromExpression(path, PlaceholderContext.of(this));
     }
 
     /**
@@ -475,7 +566,7 @@ public interface Config extends Cloneable, PlaceholderInjectable {
      */
     default double getDoubleFromExpression(@NotNull String path,
                                            @Nullable Player player) {
-        return NumberUtils.evaluateExpression(this.getString(path), player, this);
+        return getDoubleFromExpression(path, player, Collections.emptyList());
     }
 
     /**
@@ -489,7 +580,27 @@ public interface Config extends Cloneable, PlaceholderInjectable {
     default double getDoubleFromExpression(@NotNull String path,
                                            @Nullable Player player,
                                            @NotNull Collection<AdditionalPlayer> additionalPlayers) {
-        return NumberUtils.evaluateExpression(this.getString(path), player, this, additionalPlayers);
+        return getDoubleFromExpression(path, new PlaceholderContext(
+                player,
+                null,
+                this,
+                additionalPlayers
+        ));
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path    The key to fetch the value from.
+     * @param context The placeholder context.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default double getDoubleFromExpression(@NotNull String path,
+                                           @NotNull PlaceholderContext context) {
+        return Objects.requireNonNullElseGet(
+                this.getDoubleOrNull(path),
+                () -> NumberUtils.evaluateExpression(this.getString(path), context.withInjectableContext(this))
+        );
     }
 
     /**
@@ -541,6 +652,32 @@ public interface Config extends Cloneable, PlaceholderInjectable {
     @Nullable
     List<? extends Config> getSubsectionsOrNull(@NotNull String path);
 
+    /**
+     * Get a big decimal from config.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or 0 if not found.
+     */
+    @NotNull
+    default BigDecimal getBigDecimal(@NotNull final String path) {
+        return Objects.requireNonNullElse(getBigDecimalOrNull(path), BigDecimal.ZERO);
+    }
+
+    /**
+     * Get a big decimal from config.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or null if not found.
+     */
+    @Nullable
+    default BigDecimal getBigDecimalOrNull(@NotNull final String path) {
+        if (this.has(path)) {
+            return new BigDecimal(this.getString(path));
+        } else {
+            return null;
+        }
+    }
+
     /**
      * Get config type.
      *

eco-api/src/main/java/com/willfp/eco/core/config/interfaces/LoadableConfig.java

@@ -29,6 +29,22 @@ public interface LoadableConfig extends Config {
      */
     void save() throws IOException;
 
+    /**
+     * Save the config asynchronously.
+     */
+    default void saveAsync() {
+        // This default implementation exists purely for backwards compatibility
+        // with legacy Config implementations that don't have saveAsync().
+        // Default eco implementations of Config have saveAsync() implemented.
+        new Thread(() -> {
+            try {
+                this.save();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }).start();
+    }
+
     /**
      * Get the config file.
      *

eco-api/src/main/java/com/willfp/eco/core/config/updating/ConfigUpdater.java

@@ -38,12 +38,16 @@ import java.lang.annotation.Target;
  * <p>
  * By having a plugin as a parameter, you shouldn't really need getInstance()
  * calls in your code.
- *
+ * <p>
  * While flexible, this can lead to long initialization times, so this feature
  * can be disabled in eco.yml with the uses-reflective-reload option.
+ *
+ * @deprecated This has been deprecated due to the poor control flow and long startup times.
  */
 @Retention(RetentionPolicy.RUNTIME)
 @Target(ElementType.METHOD)
 @Documented
+@Deprecated(since = "6.67.0", forRemoval = true)
+@SuppressWarnings("DeprecatedIsStillUsed")
 public @interface ConfigUpdater {
 }

eco-api/src/main/java/com/willfp/eco/core/data/ExtendedPersistentDataContainer.java

@@ -87,6 +87,10 @@ public interface ExtendedPersistentDataContainer {
      * @return The extended container.
      */
     static ExtendedPersistentDataContainer extend(@NotNull PersistentDataContainer base) {
+        if (base instanceof ExtendedPersistentDataContainer) {
+            return (ExtendedPersistentDataContainer) base;
+        }
+
         return Eco.get().adaptPdc(base);
     }
 

eco-api/src/main/java/com/willfp/eco/core/data/ServerProfile.java

@@ -9,6 +9,22 @@ import org.jetbrains.annotations.NotNull;
  * Profiles save automatically, so there is no need to save after changes.
  */
 public interface ServerProfile extends Profile {
+    /**
+     * Get the server ID.
+     *
+     * @return The server ID.
+     */
+    @NotNull
+    String getServerID();
+
+    /**
+     * Get the local server ID.
+     *
+     * @return The local server ID.
+     */
+    @NotNull
+    String getLocalServerID();
+
     /**
      * Load the server profile.
      *

eco-api/src/main/java/com/willfp/eco/core/data/keys/PersistentDataKey.java

@@ -29,6 +29,31 @@ public final class PersistentDataKey<T> {
      */
     private final PersistentDataKeyType<T> type;
 
+    /**
+     * If the key uses local storage.
+     */
+    private final boolean isLocal;
+
+    /**
+     * Create a new Persistent Data Key.
+     *
+     * @param key          The key.
+     * @param type         The data type.
+     * @param defaultValue The default value.
+     * @param isLocal        If the key uses local storage.
+     */
+    public PersistentDataKey(@NotNull final NamespacedKey key,
+                             @NotNull final PersistentDataKeyType<T> type,
+                             @NotNull final T defaultValue,
+                             final boolean isLocal) {
+        this.key = key;
+        this.defaultValue = defaultValue;
+        this.type = type;
+        this.isLocal = isLocal;
+
+        Eco.get().registerPersistentKey(this);
+    }
+
     /**
      * Create a new Persistent Data Key.
      *
@@ -42,6 +67,7 @@ public final class PersistentDataKey<T> {
         this.key = key;
         this.defaultValue = defaultValue;
         this.type = type;
+        this.isLocal = false;
 
         Eco.get().registerPersistentKey(this);
     }
@@ -82,6 +108,15 @@ public final class PersistentDataKey<T> {
         return this.type;
     }
 
+    /**
+     * Get if the key uses local storage.
+     *
+     * @return If the key uses local storage.
+     */
+    public boolean isLocal() {
+        return this.isLocal;
+    }
+
     /**
      * Get all persistent data keys.
      *

eco-api/src/main/java/com/willfp/eco/core/data/keys/PersistentDataKeyType.java

@@ -4,6 +4,7 @@ import com.willfp.eco.core.config.interfaces.Config;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
@@ -49,6 +50,11 @@ public final class PersistentDataKeyType<T> {
      */
     public static final PersistentDataKeyType<Config> CONFIG = new PersistentDataKeyType<>("CONFIG");
 
+    /**
+     * Big Decimal.
+     */
+    public static final PersistentDataKeyType<BigDecimal> BIG_DECIMAL = new PersistentDataKeyType<>("BIG_DECIMAL");
+
     /**
      * The name of the key type.
      */

eco-api/src/main/java/com/willfp/eco/core/display/Display.java

@@ -1,5 +1,6 @@
 package com.willfp.eco.core.display;
 
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.fast.FastItemStack;
 import com.willfp.eco.core.integrations.guidetection.GUIDetectionManager;
 import com.willfp.eco.util.NamespacedKeyUtils;
@@ -68,9 +69,11 @@ public final class Display {
 
         Display.revert(itemStack);
 
+        if (!Eco.get().getEcoPlugin().getConfigYml().getBool("display-without-meta")) {
             if (!itemStack.hasItemMeta()) {
                 return itemStack;
             }
+        }
 
         ItemStack original = itemStack.clone();
         Inventory inventory = player == null ? null : player.getOpenInventory().getTopInventory();
@@ -208,12 +211,22 @@ public final class Display {
                 new ArrayList<>()
         );
 
-        modules.removeIf(it -> it.getPluginName().equalsIgnoreCase(module.getPluginName()));
         modules.add(module);
 
         REGISTERED_MODULES.put(module.getWeight(), modules);
     }
 
+    /**
+     * Unregister a display module.
+     *
+     * @param module The module.
+     */
+    public static void unregisterDisplayModule(@NotNull final DisplayModule module) {
+        for (List<DisplayModule> modules : REGISTERED_MODULES.values()) {
+            modules.remove(module);
+        }
+    }
+
     private Display() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }

eco-api/src/main/java/com/willfp/eco/core/events/DropQueuePushEvent.java

@@ -27,7 +27,7 @@ public class DropQueuePushEvent extends PlayerEvent implements Cancellable {
     /**
      * The items.
      */
-    private final Collection<? extends ItemStack> items;
+    private Collection<? extends ItemStack> items;
 
     /**
      * The xp.
@@ -114,6 +114,15 @@ public class DropQueuePushEvent extends PlayerEvent implements Cancellable {
         return items;
     }
 
+    /**
+     * Set the items to be dropped.
+     *
+     * @param items The items.
+     */
+    public void setItems(Collection<? extends ItemStack> items) {
+        this.items = items;
+    }
+
     /**
      * Get the xp to be dropped.
      *

eco-api/src/main/java/com/willfp/eco/core/extensions/Extension.java

@@ -135,20 +135,26 @@ public abstract class Extension implements PluginLike {
     }
 
     @Override
-    public File getDataFolder() {
+    public @NotNull File getDataFolder() {
         return this.plugin.getDataFolder();
     }
 
     @Override
-    public ConfigHandler getConfigHandler() {
+    public @NotNull ConfigHandler getConfigHandler() {
         return this.plugin.getConfigHandler();
     }
 
     @Override
-    public Logger getLogger() {
+    public @NotNull Logger getLogger() {
         return this.plugin.getLogger();
     }
 
+    @Override
+    public @NotNull File getFile() {
+        Validate.notNull(metadata, "Metadata cannot be null!");
+        return this.metadata.file();
+    }
+
     /**
      * Get the plugin for the extension.
      *

eco-api/src/main/java/com/willfp/eco/core/extensions/ExtensionLoadException.java

@@ -0,0 +1,17 @@
+package com.willfp.eco.core.extensions;
+
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Generic exception in extension loading.
+ */
+public class ExtensionLoadException extends RuntimeException {
+    /**
+     * Create a new ExtensionLoadException.
+     *
+     * @param errorMessage The error message to show.
+     */
+    public ExtensionLoadException(@NotNull final String errorMessage) {
+        super(errorMessage);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/extensions/ExtensionMetadata.java

@@ -1,7 +1,10 @@
 package com.willfp.eco.core.extensions;
 
+import com.willfp.eco.core.version.Version;
 import org.jetbrains.annotations.NotNull;
 
+import java.io.File;
+
 /**
  * The extension's metadata.
  * <p>
@@ -10,9 +13,28 @@ import org.jetbrains.annotations.NotNull;
  * @param version The extension version.
  * @param name    The extension name.
  * @param author  The extension's author.
+ * @param file   The extension's file.
+ * @param minimumPluginVersion The minimum plugin version required for this extension.
  */
 public record ExtensionMetadata(@NotNull String version,
+                                @NotNull String name,
+                                @NotNull String author,
+                                @NotNull File file,
+                                @NotNull Version minimumPluginVersion) {
+    /**
+     * Legacy constructor.
+     *
+     * @param version The extension version.
+     * @param name    The extension name.
+     * @param author  The extension's author.
+     * @deprecated Use {@link ExtensionMetadata#ExtensionMetadata(String, String, String, File, Version)} instead.
+     */
+    @SuppressWarnings("ConstantConditions")
+    @Deprecated(since = "6.57.0", forRemoval = true)
+    public ExtensionMetadata(@NotNull String version,
                              @NotNull String name,
                              @NotNull String author) {
-
+        this(version, name, author, null, null);
+        throw new UnsupportedOperationException("Legacy constructor is not supported.");
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/extensions/MalformedExtensionException.java

@@ -7,7 +7,7 @@ import org.jetbrains.annotations.NotNull;
  * Missing or invalid extension.yml.
  * Invalid filetype.
  */
-public class MalformedExtensionException extends RuntimeException {
+public class MalformedExtensionException extends ExtensionLoadException {
     /**
      * Create a new MalformedExtensionException.
      *

eco-api/src/main/java/com/willfp/eco/core/fast/FastItemStack.java

@@ -164,15 +164,23 @@ public interface FastItemStack extends PersistentDataHolder {
      * The returned PersistentDataContainer will not modify the item until the tag is set.
      *
      * @return The base NBT tag.
+     * @deprecated Items are now component-based.
      */
-    PersistentDataContainer getBaseTag();
+    @Deprecated(forRemoval = true, since = "6.70.0")
+    default PersistentDataContainer getBaseTag() {
+        throw new UnsupportedOperationException("Not supported in 1.20.5+");
+    }
 
     /**
      * Set the base NBT tag (Not PublicBukkitValues, the base) from a PersistentDataContainer.
      *
      * @param container The PersistentDataContainer.
+     * @deprecated Items are now component-based.
      */
-    void setBaseTag(@Nullable PersistentDataContainer container);
+    @Deprecated(forRemoval = true, since = "6.70.0")
+    default void setBaseTag(@Nullable PersistentDataContainer container) {
+        throw new UnsupportedOperationException("Not supported in 1.20.5+");
+    }
 
     /**
      * Get the type of the item.

eco-api/src/main/java/com/willfp/eco/core/gui/menu/MenuBuilder.java

@@ -142,6 +142,26 @@ public interface MenuBuilder extends PageBuilder {
         return this.onRender((player, menu) -> menu.setState(player, Page.MAX_PAGE_KEY, pages.apply(player)));
     }
 
+    /**
+     * Set the default page.
+     *
+     * @param page The page.
+     * @return The builder.
+     */
+    default MenuBuilder defaultPage(final int page) {
+        return this.maxPages(player -> page);
+    }
+
+    /**
+     * Set the default page dynamically for a player.
+     *
+     * @param page The default page.
+     * @return The builder.
+     */
+    default MenuBuilder defaultPage(@NotNull final Function<Player, Integer> page) {
+        return this.onOpen((player, menu) -> menu.setState(player, Page.PAGE_KEY, page.apply(player)));
+    }
+
     /**
      * Add a menu close handler.
      *

eco-api/src/main/java/com/willfp/eco/core/gui/menu/MenuEventHandler.java

@@ -5,6 +5,8 @@ import org.jetbrains.annotations.NotNull;
 
 /**
  * Handles menu events.
+ *
+ * @param <T> The type of event to handle.x
  */
 public abstract class MenuEventHandler<T extends MenuEvent> {
     /**

eco-api/src/main/java/com/willfp/eco/core/gui/slot/ConfigSlot.java

@@ -86,7 +86,7 @@ public class ConfigSlot extends CustomSlot {
             for (String command : config.getStrings(configKey)) {
                 if (command.startsWith("console:")) {
                     commands.add(new CommandToDispatch(
-                            StringUtils.removePrefix("console:", command),
+                            StringUtils.removePrefix(command, "console:"),
                             true
                     ));
                 } else {

eco-api/src/main/java/com/willfp/eco/core/gui/slot/CustomSlot.java

@@ -2,6 +2,7 @@ package com.willfp.eco.core.gui.slot;
 
 import com.willfp.eco.core.gui.menu.Menu;
 import org.bukkit.entity.Player;
+import org.bukkit.event.inventory.ClickType;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -76,6 +77,15 @@ public abstract class CustomSlot implements Slot {
         return delegate;
     }
 
+    @Override
+    public boolean shouldRenderOnClick(@NotNull final ClickType clickType) {
+        if (delegate == null) {
+            throw new IllegalStateException("Custom Slot was not initialized!");
+        }
+
+        return delegate.shouldRenderOnClick(clickType);
+    }
+
     @Override
     public final int getRows() {
         return Slot.super.getRows();

eco-api/src/main/java/com/willfp/eco/core/gui/slot/Slot.java

@@ -7,6 +7,7 @@ import com.willfp.eco.core.gui.slot.functional.SlotProvider;
 import com.willfp.eco.core.items.TestableItem;
 import org.bukkit.Material;
 import org.bukkit.entity.Player;
+import org.bukkit.event.inventory.ClickType;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -92,6 +93,27 @@ public interface Slot extends GUIComponent {
         return false;
     }
 
+    /**
+     * If the slot should re-render the menu if clicked.
+     *
+     * @return If the slot should re-render.
+     * @deprecated Use {@link Slot#shouldRenderOnClick(ClickType)} instead.
+     */
+    @Deprecated(since = "6.66.0", forRemoval = true)
+    default boolean shouldRenderOnClick() {
+        return shouldRenderOnClick(ClickType.LEFT);
+    }
+
+    /**
+     * If the slot should re-render the menu if clicked.
+     *
+     * @param clickType The click type.
+     * @return If the slot should re-render.
+     */
+    default boolean shouldRenderOnClick(@NotNull final ClickType clickType) {
+        return true;
+    }
+
     @Override
     default int getRows() {
         return 1;

eco-api/src/main/java/com/willfp/eco/core/gui/slot/SlotBuilder.java

@@ -196,6 +196,7 @@ public interface SlotBuilder {
      * @deprecated Use {@link SlotBuilder#setUpdater(SlotUpdater)} instead.
      */
     @Deprecated
+    @SuppressWarnings("DeprecatedIsStillUsed")
     default SlotBuilder setModifier(@NotNull SlotModifier modifier) {
         return setUpdater((player, menu, previous) -> {
             modifier.modify(player, menu, previous);

eco-api/src/main/java/com/willfp/eco/core/integrations/IntegrationRegistry.java

@@ -17,6 +17,13 @@ import java.util.function.Supplier;
  * @param <T> The type of integration.
  */
 public class IntegrationRegistry<T extends Integration> extends Registry<T> {
+    /**
+     * Create a new integration registry.
+     */
+    public IntegrationRegistry() {
+        super();
+    }
+
     @Override
     public @NotNull T register(@NotNull final T element) {
         return executeSafely(() -> super.register(element), element);
@@ -110,11 +117,11 @@ public class IntegrationRegistry<T extends Integration> extends Registry<T> {
                                 @Nullable final R defaultValue) {
         try {
             return action.get();
-        } catch (final Exception e) {
+        } catch (final Exception | LinkageError e) {
             Eco.get().getEcoPlugin().getLogger().warning("Integration for " + integration.getPluginName() + " threw an exception!");
             Eco.get().getEcoPlugin().getLogger().warning("The integration will be disabled.");
             e.printStackTrace();
-            this.remove(integration.getPluginName());
+            this.remove(integration);
             return defaultValue;
         }
     }

eco-api/src/main/java/com/willfp/eco/core/integrations/customblocks/CustomBlocksIntegration.java

@@ -0,0 +1,24 @@
+package com.willfp.eco.core.integrations.customblocks;
+
+import com.willfp.eco.core.integrations.Integration;
+
+/**
+ * Wrapper class for custom block integrations.
+ */
+public interface CustomBlocksIntegration extends Integration {
+    /**
+     * Register all the custom block for a specific plugin into eco.
+     *
+     * @see com.willfp.eco.core.blocks.Blocks
+     */
+    default void registerAllBlocks() {
+        // Override when needed.
+    }
+
+    /**
+     * Register {@link com.willfp.eco.core.blocks.provider.BlockProvider}s.
+     */
+    default void registerProvider() {
+        // Override when needed.
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/integrations/customblocks/CustomBlocksManager.java

@@ -0,0 +1,45 @@
+package com.willfp.eco.core.integrations.customblocks;
+
+import com.willfp.eco.core.integrations.IntegrationRegistry;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Class to handle custom block integrations.
+ */
+public final class CustomBlocksManager {
+    /**
+     * A set of all registered integrations.
+     */
+    private static final IntegrationRegistry<CustomBlocksIntegration> REGISTRY = new IntegrationRegistry<>();
+
+    /**
+     * Register a new integration.
+     *
+     * @param integration The integration to register.
+     */
+    public static void register(@NotNull final CustomBlocksIntegration integration) {
+        REGISTRY.register(integration);
+    }
+
+    /**
+     * Register all the custom block for a specific plugin into eco.
+     *
+     * @see com.willfp.eco.core.blocks.Blocks
+     */
+    public static void registerAllBlocks() {
+        REGISTRY.forEachSafely(CustomBlocksIntegration::registerAllBlocks);
+    }
+
+    /**
+     * Register all the custom blocks for a specific plugin into eco.
+     *
+     * @see com.willfp.eco.core.blocks.Blocks
+     */
+    public static void registerProviders() {
+        REGISTRY.forEachSafely(CustomBlocksIntegration::registerProvider);
+    }
+
+    private CustomBlocksManager() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/integrations/placeholder/PlaceholderIntegration.java

@@ -9,7 +9,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 /**
- * Wrapper class for placeholder integrations.
+ * Wrapper class for arguments integrations.
  */
 public interface PlaceholderIntegration extends Integration {
     /**

eco-api/src/main/java/com/willfp/eco/core/integrations/placeholder/PlaceholderManager.java

@@ -1,21 +1,15 @@
 package com.willfp.eco.core.integrations.placeholder;
 
-import com.github.benmanes.caffeine.cache.Cache;
-import com.github.benmanes.caffeine.cache.Caffeine;
-import com.github.benmanes.caffeine.cache.LoadingCache;
+import com.google.common.collect.ImmutableSet;
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.map.DefaultMap;
 import com.willfp.eco.core.placeholder.AdditionalPlayer;
-import com.willfp.eco.core.placeholder.DynamicPlaceholder;
 import com.willfp.eco.core.placeholder.InjectablePlaceholder;
 import com.willfp.eco.core.placeholder.Placeholder;
 import com.willfp.eco.core.placeholder.PlaceholderInjectable;
-import com.willfp.eco.core.placeholder.PlayerDynamicPlaceholder;
-import com.willfp.eco.core.placeholder.PlayerPlaceholder;
-import com.willfp.eco.core.placeholder.PlayerStaticPlaceholder;
-import com.willfp.eco.core.placeholder.PlayerlessPlaceholder;
-import com.willfp.eco.core.placeholder.StaticPlaceholder;
-import com.willfp.eco.util.StringUtils;
-import org.apache.commons.lang.Validate;
+import com.willfp.eco.core.placeholder.RegistrablePlaceholder;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -23,58 +17,34 @@ import org.jetbrains.annotations.Nullable;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
-import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
-import java.util.Map;
-import java.util.Optional;
+import java.util.Objects;
 import java.util.Set;
-import java.util.concurrent.TimeUnit;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 /**
- * Class to handle placeholder integrations.
+ * Class to handle arguments integrations.
  */
 public final class PlaceholderManager {
     /**
      * All registered placeholders.
      */
-    private static final Map<EcoPlugin, Map<Pattern, Placeholder>> REGISTERED_PLACEHOLDERS = new HashMap<>();
+    private static final DefaultMap<EcoPlugin, Set<Placeholder>> REGISTERED_PLACEHOLDERS = new DefaultMap<>(HashSet::new);
 
     /**
-     * All registered placeholder integrations.
+     * All registered arguments integrations.
      */
     private static final Set<PlaceholderIntegration> REGISTERED_INTEGRATIONS = new HashSet<>();
 
-    /**
-     * Placeholder Lookup Cache.
-     */
-    private static final Cache<PlaceholderLookup, Optional<Placeholder>> PLACEHOLDER_LOOKUP_CACHE = Caffeine.newBuilder()
-            .expireAfterWrite(1, TimeUnit.SECONDS)
-            .build();
-
-    /**
-     * Placeholder Cache.
-     */
-    private static final LoadingCache<EntryWithPlayer, String> PLACEHOLDER_CACHE = Caffeine.newBuilder()
-            .expireAfterWrite(50, TimeUnit.MILLISECONDS)
-            .build(key -> key.entry.getValue(key.player));
-
-    /**
-     * Dynamic Placeholder Cache.
-     */
-    private static final LoadingCache<DynamicEntryWithPlayer, String> DYNAMIC_PLACEHOLDER_CACHE = Caffeine.newBuilder()
-            .expireAfterWrite(50, TimeUnit.MILLISECONDS)
-            .build(key -> key.entry.getValue(key.args, key.player));
-
     /**
      * The default PlaceholderAPI pattern; brought in for compatibility.
      */
     private static final Pattern PATTERN = Pattern.compile("%([^% ]+)%");
 
     /**
-     * Empty injectable object.
+     * Empty injectableContext object.
      */
     public static final PlaceholderInjectable EMPTY_INJECTABLE = new PlaceholderInjectable() {
         @Override
@@ -105,97 +75,69 @@ public final class PlaceholderManager {
     }
 
     /**
-     * Register a placeholder.
+     * Register a arguments.
      *
-     * @param placeholder The placeholder to register.
+     * @param placeholder The arguments to register.
+     * @deprecated Use {@link #registerPlaceholder(RegistrablePlaceholder)} instead.
      */
+    @Deprecated(since = "6.56.0", forRemoval = true)
     public static void registerPlaceholder(@NotNull final Placeholder placeholder) {
-        if (placeholder instanceof StaticPlaceholder || placeholder instanceof PlayerStaticPlaceholder) {
-            throw new IllegalArgumentException("Static placeholders cannot be registered!");
+        if (!(placeholder instanceof RegistrablePlaceholder)) {
+            throw new IllegalArgumentException("Placeholder must be RegistrablePlaceholder!");
         }
 
-        Map<Pattern, Placeholder> pluginPlaceholders = REGISTERED_PLACEHOLDERS
-                .getOrDefault(placeholder.getPlugin(), new HashMap<>());
-
-        pluginPlaceholders.put(placeholder.getPattern(), placeholder);
-
-        REGISTERED_PLACEHOLDERS.put(placeholder.getPlugin(), pluginPlaceholders);
+        registerPlaceholder((RegistrablePlaceholder) placeholder);
     }
 
     /**
-     * Get the result of a placeholder with respect to a player.
+     * Register a arguments.
      *
-     * @param player     The player to get the result from.
-     * @param identifier The placeholder identifier.
-     * @return The value of the placeholder.
-     * @deprecated Specify a plugin to get the result from.
+     * @param placeholder The arguments to register.
      */
-    @Deprecated(since = "6.52.2", forRemoval = true)
-    @SuppressWarnings("unused")
-    public static String getResult(@Nullable final Player player,
-                                   @NotNull final String identifier) {
-        throw new UnsupportedOperationException("Please specify a plugin to get the result from!");
+    public static void registerPlaceholder(@NotNull final RegistrablePlaceholder placeholder) {
+        // Storing as immutable set leads to slower times to register placeholders, but much
+        // faster times to access registrations.
+        Set<Placeholder> pluginPlaceholders = new HashSet<>(REGISTERED_PLACEHOLDERS.get(placeholder.getPlugin()));
+        pluginPlaceholders.removeIf(p -> p.getPattern().equals(placeholder.getPattern()));
+        pluginPlaceholders.add(placeholder);
+        REGISTERED_PLACEHOLDERS.put(placeholder.getPlugin(), ImmutableSet.copyOf(pluginPlaceholders));
     }
 
     /**
      * Get the result of a placeholder with respect to a player.
      *
      * @param player     The player to get the result from.
-     * @param identifier The placeholder identifier.
-     * @param plugin     The plugin for the placeholder.
-     * @return The value of the placeholder.
+     * @param identifier The placeholder args.
+     * @param plugin     The plugin for the arguments.
+     * @return The value of the arguments.
      */
     @NotNull
     public static String getResult(@Nullable final Player player,
                                    @NotNull final String identifier,
-                                   @NotNull final EcoPlugin plugin) {
-        Validate.notNull(plugin, "Plugin cannot be null!");
-
-        // This is really janky, and it sucks, but it works so?
-        // Compensating for regex being slow so that's why we get it.
-        Placeholder placeholder = PLACEHOLDER_LOOKUP_CACHE.get(
-                new PlaceholderLookup(identifier, plugin),
-                (it) -> {
-                    // I hate the streams API.
-                    return REGISTERED_PLACEHOLDERS
-                            .getOrDefault(plugin, new HashMap<>())
-                            .entrySet()
-                            .stream().filter(entry -> entry.getKey().matcher(identifier).matches())
-                            .map(Map.Entry::getValue)
-                            .findFirst();
-                }
-        ).orElse(null);
-
-        if (placeholder == null) {
-            return "";
+                                   @Nullable final EcoPlugin plugin) {
+        return Objects.requireNonNullElse(
+                getResult(
+                        plugin,
+                        identifier,
+                        new PlaceholderContext(player)
+                ),
+                ""
+        );
     }
 
-        /*
-        This code here is *really* not very good. It's mega externalized logic hacked
-        together and made worse by the addition of dynamic placeholders. But it works,
-        and it means I don't have to rewrite the whole placeholder system. So it's
-        good enough for me.
+    /**
+     * Get the result of a placeholder given a plugin and arguments.
+     *
+     * @param plugin  The plugin for the placeholder.
+     * @param args    The arguments.
+     * @param context The context.
+     * @return The value of the arguments.
      */
-
-        if (placeholder instanceof PlayerPlaceholder playerPlaceholder) {
-            if (player == null) {
-                return "";
-            } else {
-                return PLACEHOLDER_CACHE.get(new EntryWithPlayer(playerPlaceholder, player));
-            }
-        } else if (placeholder instanceof PlayerlessPlaceholder playerlessPlaceholder) {
-            return playerlessPlaceholder.getValue();
-        } else if (placeholder instanceof PlayerDynamicPlaceholder playerDynamicPlaceholder) {
-            if (player == null) {
-                return "";
-            } else {
-                return DYNAMIC_PLACEHOLDER_CACHE.get(new DynamicEntryWithPlayer(playerDynamicPlaceholder, identifier, player));
-            }
-        } else if (placeholder instanceof DynamicPlaceholder dynamicPlaceholder) {
-            return dynamicPlaceholder.getValue(identifier);
-        } else {
-            return "";
-        }
+    @Nullable
+    public static String getResult(@Nullable final EcoPlugin plugin,
+                                   @NotNull final String args,
+                                   @NotNull final PlaceholderContext context) {
+        return Eco.get().getPlaceholderValue(plugin, args, context);
     }
 
     /**
@@ -204,7 +146,11 @@ public final class PlaceholderManager {
      * @param text   The text that may contain placeholders to translate.
      * @param player The player to translate the placeholders with respect to.
      * @return The text, translated.
+     * @deprecated Use {@link #translatePlaceholders(String, PlaceholderContext)} instead.
      */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    @SuppressWarnings("DeprecatedIsStillUsed")
     public static String translatePlaceholders(@NotNull final String text,
                                                @Nullable final Player player) {
         return translatePlaceholders(text, player, EMPTY_INJECTABLE);
@@ -215,13 +161,25 @@ public final class PlaceholderManager {
      *
      * @param text    The text that may contain placeholders to translate.
      * @param player  The player to translate the placeholders with respect to.
-     * @param context The injectable context.
+     * @param context The injectableContext parseContext.
      * @return The text, translated.
+     * @deprecated Use {@link #translatePlaceholders(String, PlaceholderContext)} instead.
      */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    @SuppressWarnings("DeprecatedIsStillUsed")
     public static String translatePlaceholders(@NotNull final String text,
                                                @Nullable final Player player,
                                                @NotNull final PlaceholderInjectable context) {
-        return translatePlaceholders(text, player, context, new ArrayList<>());
+        return translatePlaceholders(
+                text,
+                new PlaceholderContext(
+                        player,
+                        null,
+                        context,
+                        new ArrayList<>()
+                )
+        );
     }
 
     /**
@@ -229,84 +187,51 @@ public final class PlaceholderManager {
      *
      * @param text              The text that may contain placeholders to translate.
      * @param player            The player to translate the placeholders with respect to.
-     * @param context           The injectable context.
+     * @param context           The injectableContext parseContext.
      * @param additionalPlayers Additional players to translate placeholders for.
      * @return The text, translated.
+     * @deprecated Use {@link #translatePlaceholders(String, PlaceholderContext)} instead.
      */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    @SuppressWarnings("DeprecatedIsStillUsed")
     public static String translatePlaceholders(@NotNull final String text,
                                                @Nullable final Player player,
                                                @NotNull final PlaceholderInjectable context,
                                                @NotNull final Collection<AdditionalPlayer> additionalPlayers) {
-        String processed = text;
-
-        /*
-
-        Why am I doing statics at the start, but player statics at the end?
-
-        Additional players let you use something like victim as a player to parse in relation to,
-        for example doing %victim_player_health%, which would parse the health of the victim.
-
-        However, something like libreforge will also inject %victim_max_health%, which is unrelated
-        to additional players, and instead holds a constant value. So, eco saw this, smartly thought
-        "ah, it's an additional player, let's parse it", and then tried to parse %max_health% with
-        relation to the victim, which resolved to zero. So, we have to parse statics and player statics
-        that might include a prefix first, then additional players, then player statics with the support
-        of additional players.
-
-        This was a massive headache and took so many reports before I clocked what was going on.
-
-        Oh well, at least it's fixed now.
-
-         */
-
-
-        for (InjectablePlaceholder injection : context.getPlaceholderInjections()) {
-            if (injection instanceof StaticPlaceholder placeholder) {
-                processed = processed.replace("%" + placeholder.getIdentifier() + "%", placeholder.getValue());
-            } else if (injection instanceof PlayerStaticPlaceholder placeholder && player != null) {
-                processed = processed.replace("%" + placeholder.getIdentifier() + "%", placeholder.getValue(player));
-            }
-        }
-
-        // Prevent running 2 scans if there are no additional players.
-        if (!additionalPlayers.isEmpty()) {
-            List<String> found = findPlaceholdersIn(text);
-
-            for (AdditionalPlayer additionalPlayer : additionalPlayers) {
-                for (String placeholder : found) {
-                    String prefix = "%" + additionalPlayer.getIdentifier() + "_";
-
-                    if (placeholder.startsWith(prefix)) {
-                        processed = processed.replace(
-                                placeholder,
-                                translatePlaceholders(
-                                        "%" + StringUtils.removePrefix(prefix, placeholder),
-                                        additionalPlayer.getPlayer()
+        return translatePlaceholders(
+                text,
+                new PlaceholderContext(
+                        player,
+                        null,
+                        context,
+                        additionalPlayers
                 )
         );
     }
-                }
-            }
+
+    /**
+     * Translate all placeholders without a placeholder context.
+     *
+     * @param text The text that may contain placeholders to translate.
+     * @return The text, translated.
+     */
+    @NotNull
+    public static String translatePlaceholders(@NotNull final String text) {
+        return Eco.get().translatePlaceholders(text, PlaceholderContext.EMPTY);
     }
 
-        // Only run jank code if there are no integrations.
-        if (REGISTERED_INTEGRATIONS.isEmpty()) {
-            processed = setWithoutIntegration(processed, player);
-        }
-
-        for (PlaceholderIntegration integration : REGISTERED_INTEGRATIONS) {
-            processed = integration.translate(processed, player);
-        }
-
-        // DON'T REMOVE THIS, IT'S NOT DUPLICATE CODE.
-        for (InjectablePlaceholder injection : context.getPlaceholderInjections()) {
-            // Do I know this is a bad way of doing this? Yes.
-            if (injection instanceof PlayerStaticPlaceholder placeholder && player != null) {
-                processed = processed.replace("%" + placeholder.getIdentifier() + "%", placeholder.getValue(player));
-            }
-        }
-
-        return processed;
+    /**
+     * Translate all placeholders in a translation context.
+     *
+     * @param text    The text that may contain placeholders to translate.
+     * @param context The translation context.
+     * @return The text, translated.
+     */
+    @NotNull
+    public static String translatePlaceholders(@NotNull final String text,
+                                               @NotNull final PlaceholderContext context) {
+        return Eco.get().translatePlaceholders(text, context);
     }
 
     /**
@@ -331,108 +256,22 @@ public final class PlaceholderManager {
     }
 
     /**
-     * Set placeholders without any integrations.
-     * <p>
-     * This is fallback if for some reason you don't have PAPI installed.
-     * It's a cut-down version of the actual PAPI code, and I don't
-     * really know how it works.
-     * <p>
-     * Original source
-     * <a href="https://github.com/PlaceholderAPI/PlaceholderAPI/blob/master/src/main/java/me/clip/placeholderapi/replacer/CharsReplacer.java">here</a>.
+     * Get all registered placeholder integrations.
      *
-     * @param text   The text.
-     * @param player The player.
-     * @return The text.
+     * @return The integrations.
      */
-    private static String setWithoutIntegration(@NotNull final String text,
-                                                @Nullable final Player player) {
-        char[] chars = text.toCharArray();
-        StringBuilder builder = new StringBuilder(text.length());
-        StringBuilder identifier = new StringBuilder();
-        StringBuilder parameters = new StringBuilder();
-
-        for (int i = 0; i < chars.length; i++) {
-            char currentChar = chars[i];
-            if (currentChar == '%' && i + 1 < chars.length) {
-                boolean identified = false;
-                boolean badPlaceholder = true;
-                boolean hadSpace = false;
-
-                while (true) {
-                    i++;
-                    if (i >= chars.length) {
-                        break;
+    public static Set<PlaceholderIntegration> getRegisteredIntegrations() {
+        return Set.copyOf(REGISTERED_INTEGRATIONS);
     }
 
-                    char p = chars[i];
-                    if (p == ' ' && !identified) {
-                        hadSpace = true;
-                        break;
-                    }
-
-                    if (p == '%') {
-                        badPlaceholder = false;
-                        break;
-                    }
-
-                    if (p == '_' && !identified) {
-                        identified = true;
-                    } else if (identified) {
-                        parameters.append(p);
-                    } else {
-                        identifier.append(p);
-                    }
-                }
-
-                String pluginName = identifier.toString().toLowerCase();
-                EcoPlugin plugin = EcoPlugin.getPlugin(pluginName);
-                String placeholderIdentifier = parameters.toString();
-                identifier.setLength(0);
-                parameters.setLength(0);
-                if (badPlaceholder) {
-                    builder.append('%').append(pluginName);
-                    if (identified) {
-                        builder.append('_').append(placeholderIdentifier);
-                    }
-
-                    if (hadSpace) {
-                        builder.append(' ');
-                    }
-                } else {
-                    if (plugin == null) {
-                        builder.append('%').append(pluginName);
-
-                        if (identified) {
-                            builder.append('_');
-                        }
-
-                        builder.append(placeholderIdentifier).append('%');
-                    } else {
-                        builder.append(getResult(player, placeholderIdentifier, plugin));
-                    }
-                }
-            } else {
-                builder.append(currentChar);
-            }
-        }
-
-        return builder.toString();
-    }
-
-    private record PlaceholderLookup(@NotNull String identifier,
-                                     @Nullable EcoPlugin plugin) {
-
-    }
-
-    private record EntryWithPlayer(@NotNull PlayerPlaceholder entry,
-                                   @NotNull Player player) {
-
-    }
-
-    private record DynamicEntryWithPlayer(@NotNull PlayerDynamicPlaceholder entry,
-                                          @NotNull String args,
-                                          @NotNull Player player) {
-
+    /**
+     * Get all registered placeholders for a plugin.
+     *
+     * @param plugin The plugin.
+     * @return The placeholders.
+     */
+    public static Set<Placeholder> getRegisteredPlaceholders(@NotNull final EcoPlugin plugin) {
+        return REGISTERED_PLACEHOLDERS.get(plugin);
     }
 
     private PlaceholderManager() {

eco-api/src/main/java/com/willfp/eco/core/items/CustomItem.java

@@ -1,7 +1,6 @@
 package com.willfp.eco.core.items;
 
 import com.willfp.eco.core.Eco;
-import org.bukkit.Bukkit;
 import org.bukkit.NamespacedKey;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -55,7 +54,7 @@ public class CustomItem implements TestableItem {
          */
         Eco.get().getEcoPlugin().getScheduler().runLater(() -> {
             if (!matches(getItem())) {
-                Bukkit.getLogger().severe("Item with key " + key + " is invalid!");
+                Eco.get().getEcoPlugin().getLogger().severe("Item with key " + key + " is invalid!");
             }
         }, 1);
     }

eco-api/src/main/java/com/willfp/eco/core/items/Items.java

@@ -6,6 +6,7 @@ import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.fast.FastItemStack;
 import com.willfp.eco.core.items.args.LookupArgParser;
 import com.willfp.eco.core.items.provider.ItemProvider;
+import com.willfp.eco.core.items.tag.ItemTag;
 import com.willfp.eco.core.recipe.parts.EmptyTestableItem;
 import com.willfp.eco.core.recipe.parts.MaterialTestableItem;
 import com.willfp.eco.core.recipe.parts.ModifiedTestableItem;
@@ -92,6 +93,11 @@ public final class Items {
      */
     private static final Map<String, Material> FRIENDLY_MATERIAL_NAMES = new HashMap<>();
 
+    /**
+     * All tags.
+     */
+    private static final Map<String, ItemTag> TAGS = new HashMap<>();
+
     /**
      * Register a new custom item.
      *
@@ -216,7 +222,20 @@ public final class Items {
 
         String[] split = args[0].toLowerCase().split(":");
 
-        if (split.length == 1) {
+        String base = split[0];
+        boolean isTag = base.startsWith("#");
+
+        if (isTag) {
+            String tag = base.substring(1);
+            ItemTag itemTag = TAGS.get(tag);
+
+            if (itemTag == null) {
+                return new EmptyTestableItem();
+            }
+            item = itemTag.toTestableItem();
+        }
+
+        if (split.length == 1 && !isTag) {
             String itemType = args[0];
             boolean isWildcard = itemType.startsWith("*");
             if (isWildcard) {
@@ -229,7 +248,7 @@ public final class Items {
             item = isWildcard ? new UnrestrictedMaterialTestableItem(material) : new MaterialTestableItem(material);
         }
 
-        if (split.length == 2) {
+        if (split.length == 2 && !isTag) {
             String namespace = split[0];
             String keyID = split[1];
             NamespacedKey namespacedKey = NamespacedKeyUtils.create(namespace, keyID);
@@ -273,7 +292,7 @@ public final class Items {
         Legacy namespace:id:amount format
         This has been superseded by namespace:id amount
          */
-        if (split.length == 3) {
+        if (split.length == 3 && !isTag) {
             TestableItem part = REGISTRY.get(NamespacedKeyUtils.create(split[0], split[1]));
             if (part == null) {
                 return new EmptyTestableItem();
@@ -305,7 +324,8 @@ public final class Items {
 
         List<Predicate<ItemStack>> predicates = new ArrayList<>();
 
-        for (LookupArgParser argParser : ARG_PARSERS) {
+        for (
+                LookupArgParser argParser : ARG_PARSERS) {
             Predicate<ItemStack> predicate = argParser.parseArguments(modifierArgs, meta);
             if (predicate != null) {
                 predicates.add(argParser.parseArguments(modifierArgs, meta));
@@ -515,8 +535,11 @@ public final class Items {
      *
      * @param itemStack The ItemStack.
      * @return The base NBT.
+     * @deprecated Items are now component-based.
      */
     @NotNull
+    @Deprecated(since = "6.70.0", forRemoval = true)
+    @SuppressWarnings("removal")
     public static PersistentDataContainer getBaseNBT(@NotNull final ItemStack itemStack) {
         return FastItemStack.wrap(itemStack).getBaseTag();
     }
@@ -527,8 +550,11 @@ public final class Items {
      * @param itemStack The ItemStack.
      * @param container The base NBT tag.
      * @return The ItemStack, modified. Not required to use, as this modifies the instance.¬
+     * @deprecated Items are now component-based.
      */
     @NotNull
+    @Deprecated(since = "6.70.0", forRemoval = true)
+    @SuppressWarnings("removal")
     public static ItemStack setBaseNBT(@NotNull final ItemStack itemStack,
                                        @Nullable final PersistentDataContainer container) {
         FastItemStack fis = FastItemStack.wrap(itemStack);
@@ -604,6 +630,24 @@ public final class Items {
         return false;
     }
 
+    /**
+     * Register a new item tag.
+     *
+     * @param tag The tag.
+     */
+    public static void registerTag(@NotNull final ItemTag tag) {
+        TAGS.put(tag.getIdentifier(), tag);
+    }
+
+    /**
+     * Get all tags.
+     *
+     * @return All tags.
+     */
+    public static Collection<ItemTag> getTags() {
+        return TAGS.values();
+    }
+
     private Items() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }

eco-api/src/main/java/com/willfp/eco/core/items/tag/CustomItemTag.java

@@ -0,0 +1,29 @@
+package com.willfp.eco.core.items.tag;
+
+import org.bukkit.NamespacedKey;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * A custom item tag.
+ */
+public abstract class CustomItemTag implements ItemTag {
+    /**
+     * The key.
+     */
+    private final NamespacedKey key;
+
+    /**
+     * Create a new custom item tag.
+     *
+     * @param key         The key.
+     */
+    public CustomItemTag(@NotNull final NamespacedKey key) {
+        this.key = key;
+    }
+
+    @Override
+    @NotNull
+    public String getIdentifier() {
+        return key.toString();
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/items/tag/ItemTag.java

@@ -0,0 +1,66 @@
+package com.willfp.eco.core.items.tag;
+
+import com.willfp.eco.core.items.TestableItem;
+import org.bukkit.Material;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * A group of items that share a common trait.
+ */
+public interface ItemTag {
+    /**
+     * Get the identifier of the tag.
+     *
+     * @return The identifier.
+     */
+    @NotNull
+    String getIdentifier();
+
+    /**
+     * Check if an item matches the tag.
+     *
+     * @param itemStack The item to check.
+     * @return If the item matches the tag.
+     */
+    boolean matches(@NotNull ItemStack itemStack);
+
+    /**
+     * Get an example item.
+     *
+     * @return The example item.
+     */
+    @Nullable
+    default ItemStack getExampleItem() {
+        return null;
+    }
+
+    /**
+     * Convert this tag to a testable item.
+     *
+     * @return The testable item.
+     */
+    @NotNull
+    default TestableItem toTestableItem() {
+        return new TestableItem() {
+            @Override
+            public boolean matches(@Nullable final ItemStack itemStack) {
+                return itemStack != null && ItemTag.this.matches(itemStack);
+            }
+
+            @Override
+            public @NotNull ItemStack getItem() {
+                ItemStack example = ItemTag.this.getExampleItem();
+                return example == null ? new ItemStack(Material.STONE) : example;
+            }
+
+            @Override
+            public String toString() {
+                return "ItemTagTestableItem{" +
+                        "tag=" + ItemTag.this.getIdentifier() +
+                        '}';
+            }
+        };
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/items/tag/VanillaItemTag.java

@@ -0,0 +1,58 @@
+package com.willfp.eco.core.items.tag;
+
+import org.bukkit.Material;
+import org.bukkit.Tag;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * A vanilla item tag.
+ */
+public final class VanillaItemTag implements ItemTag {
+    /**
+     * The identifier.
+     */
+    private final String identifier;
+
+    /**
+     * The tag.
+     */
+    private final Tag<Material> tag;
+
+    /**
+     * Create a new vanilla item tag.
+     *
+     * @param identifier The identifier.
+     * @param tag        The tag.
+     */
+    public VanillaItemTag(@NotNull final String identifier,
+                          @NotNull final Tag<Material> tag) {
+        this.identifier = identifier;
+        this.tag = tag;
+    }
+
+    /**
+     * Get the tag.
+     *
+     * @return The tag.
+     */
+    public Tag<Material> getTag() {
+        return tag;
+    }
+
+    @Override
+    @NotNull
+    public String getIdentifier() {
+        return identifier;
+    }
+
+    @Override
+    public boolean matches(@NotNull final ItemStack itemStack) {
+        return tag.isTagged(itemStack.getType());
+    }
+
+    @Override
+    public @NotNull ItemStack getExampleItem() {
+        return new ItemStack(tag.getValues().stream().findFirst().orElse(Material.STONE));
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/map/DefaultMap.java

@@ -150,7 +150,7 @@ public class DefaultMap<K, V> implements Map<K, V> {
      */
     @NotNull
     public static <K, K1, V> DefaultMap<K, Map<K1, V>> createNestedMap() {
-        return new DefaultMap<>(new HashMap<>());
+        return new DefaultMap<>(HashMap::new);
     }
 
     /**
@@ -163,6 +163,6 @@ public class DefaultMap<K, V> implements Map<K, V> {
      */
     @NotNull
     public static <K, K1, V> DefaultMap<K, ListMap<K1, V>> createNestedListMap() {
-        return new DefaultMap<>(new ListMap<>());
+        return new DefaultMap<>(ListMap::new);
     }
 }

eco-api/src/main/java/com/willfp/eco/core/math/MathContext.java

@@ -3,27 +3,25 @@ package com.willfp.eco.core.math;
 import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
 import com.willfp.eco.core.placeholder.AdditionalPlayer;
 import com.willfp.eco.core.placeholder.PlaceholderInjectable;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Objects;
 
 /**
- * Represents a context to do math in.
+ * Represents a context to parse math in.
  *
- * @param injectableContext The PlaceholderInjectable context.
- * @param player            The player.
- * @param additionalPlayers The additional players.
+ * @deprecated Use {@link PlaceholderContext} instead.
  */
-public record MathContext(
-        @NotNull PlaceholderInjectable injectableContext,
-        @Nullable Player player,
-        @NotNull Collection<AdditionalPlayer> additionalPlayers
-) {
+@SuppressWarnings("DeprecatedIsStillUsed")
+@Deprecated(since = "6.56.0", forRemoval = true)
+public class MathContext {
     /**
-     * Empty math context.
+     * Returns an empty math parseContext.
      */
     public static final MathContext EMPTY = new MathContext(
             PlaceholderManager.EMPTY_INJECTABLE,
@@ -32,9 +30,157 @@ public record MathContext(
     );
 
     /**
-     * Create MathContext of a PlaceholderInjectable context.
+     * The PlaceholderInjectable parse context.
+     */
+    @NotNull
+    private final PlaceholderInjectable injectableContext;
+
+    /**
+     * The player.
+     */
+    @Nullable
+    private final Player player;
+
+    /**
+     * The additional players.
+     */
+    @NotNull
+    private final Collection<AdditionalPlayer> additionalPlayers;
+
+    /**
+     * Constructs a new MathContext with the given parameters.
      *
-     * @param injectableContext The PlaceholderInjectable context.
+     * @param injectableContext The PlaceholderInjectable parseContext.
+     * @param player            The player.
+     * @param additionalPlayers The additional players.
+     */
+    public MathContext(@NotNull PlaceholderInjectable injectableContext,
+                       @Nullable Player player,
+                       @NotNull Collection<AdditionalPlayer> additionalPlayers) {
+        this.injectableContext = injectableContext;
+        this.player = player;
+        this.additionalPlayers = additionalPlayers;
+    }
+
+    /**
+     * Returns the PlaceholderInjectable parse context.
+     * <p>
+     * Duplicate method because MathContext used to be a record.
+     *
+     * @return The injectable context.
+     * @deprecated Use {@link #getInjectableContext()} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    public PlaceholderInjectable injectableContext() {
+        return injectableContext;
+    }
+
+    /**
+     * Returns the PlaceholderInjectable parse context.
+     *
+     * @return The injectable context.
+     */
+    @NotNull
+    public PlaceholderInjectable getInjectableContext() {
+        return injectableContext;
+    }
+
+    /**
+     * Returns the player.
+     * <p>
+     * Duplicate method because MathContext used to be a record.
+     *
+     * @return The player.
+     * @deprecated Use {@link #getPlayer()} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @Nullable
+    public Player player() {
+        return player;
+    }
+
+    /**
+     * Returns the player.
+     *
+     * @return The player.
+     */
+    @Nullable
+    public Player getPlayer() {
+        return player;
+    }
+
+    /**
+     * Returns the additional players.
+     * <p>
+     * Duplicate method because MathContext used to be a record.
+     *
+     * @return The additional players.
+     * @deprecated Use {@link #getAdditionalPlayers()} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    public Collection<AdditionalPlayer> additionalPlayers() {
+        return additionalPlayers;
+    }
+
+    /**
+     * Returns the additional players.
+     *
+     * @return The additional players.
+     */
+    @NotNull
+    public Collection<AdditionalPlayer> getAdditionalPlayers() {
+        return additionalPlayers;
+    }
+
+    /**
+     * Convert to PlaceholderContext.
+     *
+     * @return The PlaceholderContext.
+     */
+    @NotNull
+    public PlaceholderContext toPlaceholderContext() {
+        return new PlaceholderContext(
+                this.player,
+                null,
+                this.injectableContext,
+                this.additionalPlayers
+        );
+    }
+
+    @Override
+    public String toString() {
+        return "MathContext{" +
+                "injectableContext=" + injectableContext +
+                ", player=" + player +
+                ", additionalPlayers=" + additionalPlayers +
+                '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (!(o instanceof MathContext that)) {
+            return false;
+        }
+
+        return injectableContext.equals(that.injectableContext) &&
+                Objects.equals(player, that.player) &&
+                additionalPlayers.equals(that.additionalPlayers);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(injectableContext, player, additionalPlayers);
+    }
+
+    /**
+     * Create MathContext of a PlaceholderInjectable parseContext.
+     *
+     * @param injectableContext The PlaceholderInjectable parseContext.
      * @return The MathContext.
      */
     public static MathContext of(@NotNull final PlaceholderInjectable injectableContext) {
@@ -48,16 +194,16 @@ public record MathContext(
     /**
      * Copy a MathContext with a player.
      *
-     * @param context The context.
+     * @param context The parseContext.
      * @param player  The player.
      * @return The new MathContext.
      */
     public static MathContext copyWithPlayer(@NotNull final MathContext context,
                                              @Nullable final Player player) {
         return new MathContext(
-                context.injectableContext(),
+                context.injectableContext,
                 player,
-                context.additionalPlayers()
+                context.additionalPlayers
         );
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/DynamicPlaceholder.java

@@ -1,7 +1,7 @@
 package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.EcoPlugin;
-import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -12,24 +12,24 @@ import java.util.regex.Pattern;
 /**
  * A placeholder that does not require a player and supports dynamic styles.
  */
-public final class DynamicPlaceholder implements Placeholder {
+public final class DynamicPlaceholder implements RegistrablePlaceholder {
     /**
-     * The placeholder pattern.
+     * The arguments pattern.
      */
     private final Pattern pattern;
 
     /**
-     * The function to retrieve the output of the placeholder.
+     * The function to retrieve the output of the arguments.
      */
-    private final Function<String, String> function;
+    private final Function<@NotNull String, @Nullable String> function;
 
     /**
-     * The plugin for the placeholder.
+     * The plugin for the arguments.
      */
     private final EcoPlugin plugin;
 
     /**
-     * Create a new dynamic placeholder.
+     * Create a new dynamic arguments.
      *
      * @param plugin   The plugin.
      * @param pattern  The pattern.
@@ -37,31 +37,33 @@ public final class DynamicPlaceholder implements Placeholder {
      */
     public DynamicPlaceholder(@NotNull final EcoPlugin plugin,
                               @NotNull final Pattern pattern,
-                              @NotNull final Function<String, String> function) {
+                              @NotNull final Function<@NotNull String, @Nullable String> function) {
         this.plugin = plugin;
         this.pattern = pattern;
         this.function = function;
     }
 
-    /**
-     * Get the value of the placeholder.
-     *
-     * @param args The args.
-     * @return The value.
-     */
-    @NotNull
-    public String getValue(@NotNull final String args) {
+    @Override
+    @Nullable
+    public String getValue(@NotNull final String args,
+                           @NotNull final PlaceholderContext context) {
         return function.apply(args);
     }
 
     /**
-     * Register the placeholder.
+     * Get the value of the arguments.
      *
-     * @return The placeholder.
+     * @param args The args.
+     * @return The value.
+     * @deprecated Use {@link #getValue(String, PlaceholderContext)} instead.
      */
-    public DynamicPlaceholder register() {
-        PlaceholderManager.registerPlaceholder(this);
-        return this;
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    public String getValue(@NotNull final String args) {
+        return Objects.requireNonNullElse(
+                function.apply(args),
+                ""
+        );
     }
 
     @Override
@@ -69,18 +71,17 @@ public final class DynamicPlaceholder implements Placeholder {
         return this.plugin;
     }
 
-    @Override
-    @Deprecated
-    public @NotNull String getIdentifier() {
-        return "dynamic";
-    }
-
     @NotNull
     @Override
     public Pattern getPattern() {
         return this.pattern;
     }
 
+    @Override
+    public @NotNull DynamicPlaceholder register() {
+        return (DynamicPlaceholder) RegistrablePlaceholder.super.register();
+    }
+
     @Override
     public boolean equals(@Nullable final Object o) {
         if (this == o) {
@@ -97,6 +98,6 @@ public final class DynamicPlaceholder implements Placeholder {
 
     @Override
     public int hashCode() {
-        return Objects.hash(this.getIdentifier(), this.getPlugin());
+        return Objects.hash(this.getPattern(), this.getPlugin());
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/InjectablePlaceholder.java

@@ -1,15 +1,20 @@
 package com.willfp.eco.core.placeholder;
 
-import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.EcoPlugin;
-import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 /**
  * Placeholders that can be injected into {@link PlaceholderInjectable} objects.
  */
-public sealed interface InjectablePlaceholder extends Placeholder permits PlayerStaticPlaceholder, StaticPlaceholder {
+public interface InjectablePlaceholder extends Placeholder {
+    /**
+     * Get the plugin that holds the arguments.
+     *
+     * @return The plugin.
+     */
+    @Nullable
     @Override
-    default @NotNull EcoPlugin getPlugin() {
-        return Eco.get().getEcoPlugin();
+    default EcoPlugin getPlugin() {
+        return null;
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/Placeholder.java

@@ -1,38 +1,64 @@
 package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.util.regex.Pattern;
 
 /**
  * A placeholder represents a string that can hold a value.
  */
-public sealed interface Placeholder permits PlayerPlaceholder, PlayerlessPlaceholder,
-        DynamicPlaceholder, PlayerDynamicPlaceholder, InjectablePlaceholder {
+public interface Placeholder {
     /**
-     * Get the plugin that holds the placeholder.
+     * Get the plugin that holds the arguments.
      *
      * @return The plugin.
      */
-    @NotNull
+    @Nullable
     EcoPlugin getPlugin();
 
     /**
-     * Get the identifier for the placeholder.
+     * Get the value of the arguments.
      *
-     * @return The identifier.
+     * @param args    The args.
+     * @param context The context.
+     * @return The value.
      */
-    @NotNull
-    String getIdentifier();
+    @Nullable
+    String getValue(@NotNull String args,
+                    @NotNull PlaceholderContext context);
 
     /**
-     * Get the pattern for the placeholder.
+     * Get the pattern for the arguments.
      *
      * @return The pattern.
      */
     @NotNull
-    default Pattern getPattern() {
-        return Pattern.compile(this.getIdentifier());
+    Pattern getPattern();
+
+    /**
+     * Try to translate all instances of this placeholder in text quickly.
+     *
+     * @param text    The text to translate.
+     * @param context The context.
+     * @return The translated text.
+     */
+    default String tryTranslateQuickly(@NotNull final String text,
+                                       @NotNull final PlaceholderContext context) {
+        return text;
+    }
+
+    /**
+     * Get the identifier for the arguments.
+     *
+     * @return The identifier.
+     * @deprecated Some arguments may not have an identifier. Use {@link #getPattern()} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    default String getIdentifier() {
+        return this.getPattern().pattern();
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/PlaceholderInjectable.java

@@ -9,7 +9,7 @@ import java.util.List;
  */
 public interface PlaceholderInjectable {
     /**
-     * Inject placeholder.
+     * Inject arguments.
      *
      * @param placeholders The placeholders.
      */
@@ -18,7 +18,7 @@ public interface PlaceholderInjectable {
     }
 
     /**
-     * Inject placeholder.
+     * Inject arguments.
      *
      * @param placeholders The placeholders.
      */
@@ -29,7 +29,7 @@ public interface PlaceholderInjectable {
     /**
      * Inject placeholders.
      * <p>
-     * When implementing a PlaceholderInjectable object, override this method.
+     * If a placeholder already has the same pattern, it should be replaced.
      *
      * @param placeholders The placeholders.
      */
@@ -43,7 +43,7 @@ public interface PlaceholderInjectable {
     /**
      * Get injected placeholders.
      * <p>
-     * Override this method in implementations.
+     * This method should always return an immutable list.
      *
      * @return Injected placeholders.
      */

eco-api/src/main/java/com/willfp/eco/core/placeholder/PlayerDynamicPlaceholder.java

@@ -1,7 +1,7 @@
 package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.EcoPlugin;
-import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -11,26 +11,26 @@ import java.util.function.BiFunction;
 import java.util.regex.Pattern;
 
 /**
- * A placeholder that does not require a player and supports dynamic styles.
+ * A arguments that does not require a player and supports dynamic styles.
  */
-public final class PlayerDynamicPlaceholder implements Placeholder {
+public final class PlayerDynamicPlaceholder implements RegistrablePlaceholder {
     /**
-     * The placeholder pattern.
+     * The arguments pattern.
      */
     private final Pattern pattern;
 
     /**
-     * The function to retrieve the output of the placeholder.
+     * The function to retrieve the output of the arguments.
      */
-    private final BiFunction<String, Player, String> function;
+    private final BiFunction<@NotNull String, @NotNull Player, @Nullable String> function;
 
     /**
-     * The plugin for the placeholder.
+     * The plugin for the arguments.
      */
     private final EcoPlugin plugin;
 
     /**
-     * Create a new dynamic placeholder.
+     * Create a new dynamic arguments.
      *
      * @param plugin   The plugin.
      * @param pattern  The pattern.
@@ -38,33 +38,40 @@ public final class PlayerDynamicPlaceholder implements Placeholder {
      */
     public PlayerDynamicPlaceholder(@NotNull final EcoPlugin plugin,
                                     @NotNull final Pattern pattern,
-                                    @NotNull final BiFunction<String, Player, String> function) {
+                                    @NotNull final BiFunction<@NotNull String, @NotNull Player, @Nullable String> function) {
         this.plugin = plugin;
         this.pattern = pattern;
         this.function = function;
     }
 
-    /**
-     * Get the value of the placeholder.
-     *
-     * @param args   The args.
-     * @param player The player.
-     * @return The value.
-     */
-    @NotNull
-    public String getValue(@NotNull final String args,
-                           @NotNull final Player player) {
+    @Override
+    public @Nullable String getValue(@NotNull final String args,
+                                     @NotNull final PlaceholderContext context) {
+        Player player = context.getPlayer();
+
+        if (player == null) {
+            return null;
+        }
+
         return function.apply(args, player);
     }
 
     /**
-     * Register the placeholder.
+     * Get the value of the arguments.
      *
-     * @return The placeholder.
+     * @param args   The args.
+     * @param player The player.
+     * @return The value.
+     * @deprecated Use {@link #getValue(String, PlaceholderContext)} instead.
      */
-    public PlayerDynamicPlaceholder register() {
-        PlaceholderManager.registerPlaceholder(this);
-        return this;
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    public String getValue(@NotNull final String args,
+                           @NotNull final Player player) {
+        return Objects.requireNonNullElse(
+                function.apply(args, player),
+                ""
+        );
     }
 
     @Override
@@ -72,18 +79,17 @@ public final class PlayerDynamicPlaceholder implements Placeholder {
         return this.plugin;
     }
 
-    @Override
-    @Deprecated
-    public @NotNull String getIdentifier() {
-        return "dynamic";
-    }
-
     @NotNull
     @Override
     public Pattern getPattern() {
         return this.pattern;
     }
 
+    @Override
+    public @NotNull PlayerDynamicPlaceholder register() {
+        return (PlayerDynamicPlaceholder) RegistrablePlaceholder.super.register();
+    }
+
     @Override
     public boolean equals(@Nullable final Object o) {
         if (this == o) {
@@ -100,6 +106,6 @@ public final class PlayerDynamicPlaceholder implements Placeholder {
 
     @Override
     public int hashCode() {
-        return Objects.hash(this.getIdentifier(), this.getPlugin());
+        return Objects.hash(this.getPattern(), this.getPlugin());
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/PlayerPlaceholder.java

@@ -1,7 +1,8 @@
 package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.EcoPlugin;
-import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -11,31 +12,26 @@ import java.util.function.Function;
 import java.util.regex.Pattern;
 
 /**
- * A placeholder that requires a player.
+ * A arguments that requires a player.
  */
-public final class PlayerPlaceholder implements Placeholder {
+public final class PlayerPlaceholder implements RegistrablePlaceholder {
     /**
-     * The name of the placeholder.
-     */
-    private final String identifier;
-
-    /**
-     * The placeholder pattern.
+     * The arguments pattern.
      */
     private final Pattern pattern;
 
     /**
-     * The function to retrieve the output of the placeholder given a player.
+     * The function to retrieve the output of the arguments given a player.
      */
-    private final Function<Player, String> function;
+    private final Function<@NotNull Player, @Nullable String> function;
 
     /**
-     * The plugin for the placeholder.
+     * The plugin for the arguments.
      */
     private final EcoPlugin plugin;
 
     /**
-     * Create a new player placeholder.
+     * Create a new player arguments.
      *
      * @param plugin     The plugin.
      * @param identifier The identifier.
@@ -43,32 +39,38 @@ public final class PlayerPlaceholder implements Placeholder {
      */
     public PlayerPlaceholder(@NotNull final EcoPlugin plugin,
                              @NotNull final String identifier,
-                             @NotNull final Function<Player, String> function) {
+                             @NotNull final Function<@NotNull Player, @Nullable String> function) {
         this.plugin = plugin;
-        this.identifier = identifier;
-        this.pattern = Pattern.compile(identifier);
+        this.pattern = PatternUtils.compileLiteral(identifier);
         this.function = function;
     }
 
-    /**
-     * Get the value of the placeholder for a given player.
-     *
-     * @param player The player.
-     * @return The value.
-     */
-    @NotNull
-    public String getValue(@NotNull final Player player) {
+    @Override
+    public @Nullable String getValue(@NotNull final String args,
+                                     @NotNull final PlaceholderContext context) {
+        Player player = context.getPlayer();
+
+        if (player == null) {
+            return null;
+        }
+
         return function.apply(player);
     }
 
     /**
-     * Register the placeholder.
+     * Get the value of the arguments for a given player.
      *
-     * @return The placeholder.
+     * @param player The player.
+     * @return The value.
+     * @deprecated Use {@link #getValue(String, PlaceholderContext)} instead.
      */
-    public PlayerPlaceholder register() {
-        PlaceholderManager.registerPlaceholder(this);
-        return this;
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    public String getValue(@NotNull final Player player) {
+        return Objects.requireNonNullElse(
+                function.apply(player),
+                ""
+        );
     }
 
     @Override
@@ -76,17 +78,17 @@ public final class PlayerPlaceholder implements Placeholder {
         return this.plugin;
     }
 
-    @Override
-    public @NotNull String getIdentifier() {
-        return this.identifier;
-    }
-
     @NotNull
     @Override
     public Pattern getPattern() {
         return this.pattern;
     }
 
+    @Override
+    public @NotNull PlayerPlaceholder register() {
+        return (PlayerPlaceholder) RegistrablePlaceholder.super.register();
+    }
+
     @Override
     public boolean equals(@Nullable final Object o) {
         if (this == o) {
@@ -95,12 +97,12 @@ public final class PlayerPlaceholder implements Placeholder {
         if (!(o instanceof PlayerPlaceholder that)) {
             return false;
         }
-        return Objects.equals(this.getIdentifier(), that.getIdentifier())
+        return Objects.equals(this.getPattern(), that.getPattern())
                 && Objects.equals(this.getPlugin(), that.getPlugin());
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(this.getIdentifier(), this.getPlugin());
+        return Objects.hash(this.getPattern(), this.getPlugin());
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/PlayerStaticPlaceholder.java

@@ -1,5 +1,8 @@
 package com.willfp.eco.core.placeholder;
 
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
+import com.willfp.eco.util.StringUtils;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -13,47 +16,72 @@ import java.util.regex.Pattern;
  */
 public final class PlayerStaticPlaceholder implements InjectablePlaceholder {
     /**
-     * The name of the placeholder.
+     * The identifier.
      */
     private final String identifier;
 
     /**
-     * The placeholder pattern.
+     * The arguments pattern.
      */
     private final Pattern pattern;
 
     /**
-     * The function to retrieve the output of the placeholder.
+     * The function to retrieve the output of the arguments.
      */
-    private final Function<Player, String> function;
+    private final Function<@NotNull Player, @Nullable String> function;
 
     /**
-     * Create a new player placeholder.
+     * Create a new player arguments.
      *
      * @param identifier The identifier.
      * @param function   The function to retrieve the value.
      */
     public PlayerStaticPlaceholder(@NotNull final String identifier,
-                                   @NotNull final Function<Player, String> function) {
-        this.identifier = identifier;
-        this.pattern = Pattern.compile(identifier);
+                                   @NotNull final Function<@NotNull Player, @Nullable String> function) {
+        this.identifier = "%" + identifier + "%";
+        this.pattern = PatternUtils.compileLiteral(identifier);
         this.function = function;
     }
 
+    @Override
+    public @Nullable String getValue(@NotNull final String args,
+                                     @NotNull final PlaceholderContext context) {
+        Player player = context.getPlayer();
+
+        if (player == null) {
+            return null;
+        }
+
+        return this.getValue(player);
+    }
+
     /**
-     * Get the value of the placeholder.
+     * Get the value of the arguments.
      *
      * @param player The player.
      * @return The value.
+     * @deprecated Use {@link #getValue(String, PlaceholderContext)} instead.
      */
+    @Deprecated(since = "6.56.0", forRemoval = true)
     @NotNull
     public String getValue(@NotNull final Player player) {
-        return function.apply(player);
+        return Objects.requireNonNullElse(
+                function.apply(player),
+                ""
+        );
     }
 
     @Override
-    public @NotNull String getIdentifier() {
-        return this.identifier;
+    public String tryTranslateQuickly(@NotNull final String text,
+                                      @NotNull final PlaceholderContext context) {
+        return StringUtils.replaceQuickly(
+                text,
+                this.identifier,
+                Objects.requireNonNullElse(
+                        this.getValue(identifier, context),
+                        ""
+                )
+        );
     }
 
     @NotNull
@@ -70,11 +98,11 @@ public final class PlayerStaticPlaceholder implements InjectablePlaceholder {
         if (!(o instanceof PlayerStaticPlaceholder that)) {
             return false;
         }
-        return Objects.equals(this.getIdentifier(), that.getIdentifier());
+        return Objects.equals(this.getPattern(), that.getPattern());
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(this.getIdentifier());
+        return Objects.hash(this.getPattern());
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/PlayerlessPlaceholder.java

@@ -1,7 +1,8 @@
 package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.EcoPlugin;
-import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -10,31 +11,26 @@ import java.util.function.Supplier;
 import java.util.regex.Pattern;
 
 /**
- * A placeholder that does not require a player.
+ * A arguments that does not require a player.
  */
-public final class PlayerlessPlaceholder implements Placeholder {
+public final class PlayerlessPlaceholder implements RegistrablePlaceholder {
     /**
-     * The placeholder identifier.
-     */
-    private final String identifier;
-
-    /**
-     * The placeholder pattern.
+     * The arguments pattern.
      */
     private final Pattern pattern;
 
     /**
-     * The function to retrieve the output of the placeholder.
+     * The function to retrieve the output of the arguments.
      */
-    private final Supplier<String> function;
+    private final Supplier<@Nullable String> function;
 
     /**
-     * The plugin for the placeholder.
+     * The plugin for the arguments.
      */
     private final EcoPlugin plugin;
 
     /**
-     * Create a new player placeholder.
+     * Create a new player arguments.
      *
      * @param plugin     The plugin.
      * @param identifier The identifier.
@@ -42,30 +38,31 @@ public final class PlayerlessPlaceholder implements Placeholder {
      */
     public PlayerlessPlaceholder(@NotNull final EcoPlugin plugin,
                                  @NotNull final String identifier,
-                                 @NotNull final Supplier<String> function) {
+                                 @NotNull final Supplier<@Nullable String> function) {
         this.plugin = plugin;
-        this.identifier = identifier;
-        this.pattern = Pattern.compile(identifier);
+        this.pattern = PatternUtils.compileLiteral(identifier);
         this.function = function;
     }
 
-    /**
-     * Get the value of the placeholder.
-     *
-     * @return The value.
-     */
-    public String getValue() {
+    @Override
+    public @Nullable String getValue(@NotNull final String args,
+                                     @NotNull final PlaceholderContext context) {
         return function.get();
     }
 
     /**
-     * Register the placeholder.
+     * Get the value of the arguments.
      *
-     * @return The placeholder.
+     * @return The value.
+     * @deprecated Use {@link #getValue(String, PlaceholderContext)} instead.
      */
-    public PlayerlessPlaceholder register() {
-        PlaceholderManager.registerPlaceholder(this);
-        return this;
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    public String getValue() {
+        return Objects.requireNonNullElse(
+                this.function.get(),
+                ""
+        );
     }
 
     @Override
@@ -73,17 +70,17 @@ public final class PlayerlessPlaceholder implements Placeholder {
         return this.plugin;
     }
 
-    @Override
-    public @NotNull String getIdentifier() {
-        return this.identifier;
-    }
-
     @NotNull
     @Override
     public Pattern getPattern() {
         return this.pattern;
     }
 
+    @Override
+    public @NotNull PlayerlessPlaceholder register() {
+        return (PlayerlessPlaceholder) RegistrablePlaceholder.super.register();
+    }
+
     @Override
     public boolean equals(@Nullable final Object o) {
         if (this == o) {
@@ -92,12 +89,12 @@ public final class PlayerlessPlaceholder implements Placeholder {
         if (!(o instanceof PlayerlessPlaceholder that)) {
             return false;
         }
-        return Objects.equals(this.getIdentifier(), that.getIdentifier())
+        return Objects.equals(this.getPattern(), that.getPattern())
                 && Objects.equals(this.getPlugin(), that.getPlugin());
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(this.getIdentifier(), this.getPlugin());
+        return Objects.hash(this.getPattern(), this.getPlugin());
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/RegistrablePlaceholder.java

@@ -0,0 +1,31 @@
+package com.willfp.eco.core.placeholder;
+
+import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Represents a placeholder that can be registered.
+ */
+public interface RegistrablePlaceholder extends Placeholder {
+    /**
+     * Get the plugin that holds the arguments.
+     *
+     * @return The plugin.
+     */
+    @NotNull
+    @Override
+    EcoPlugin getPlugin();
+
+    /**
+     * Register the arguments.
+     *
+     * @return The arguments.
+     */
+    @NotNull
+    default RegistrablePlaceholder register() {
+        PlaceholderManager.registerPlaceholder(this);
+        return this;
+    }
+}
+

eco-api/src/main/java/com/willfp/eco/core/placeholder/StaticPlaceholder.java

@@ -1,5 +1,8 @@
 package com.willfp.eco.core.placeholder;
 
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
+import com.willfp.eco.util.StringUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -8,50 +11,66 @@ import java.util.function.Supplier;
 import java.util.regex.Pattern;
 
 /**
- * A placeholder that cannot be registered, and exists purely in injection.
+ * A arguments that cannot be registered, and exists purely in injection.
  */
 public final class StaticPlaceholder implements InjectablePlaceholder {
     /**
-     * The name of the placeholder.
+     * The name of the arguments.
      */
     private final String identifier;
 
     /**
-     * The placeholder pattern.
+     * The arguments pattern.
      */
     private final Pattern pattern;
 
     /**
-     * The function to retrieve the output of the placeholder.
+     * The function to retrieve the output of the arguments.
      */
-    private final Supplier<String> function;
+    private final Supplier<@Nullable String> function;
 
     /**
-     * Create a new player placeholder.
+     * Create a new player arguments.
      *
      * @param identifier The identifier.
      * @param function   The function to retrieve the value.
      */
     public StaticPlaceholder(@NotNull final String identifier,
-                             @NotNull final Supplier<String> function) {
-        this.identifier = identifier;
-        this.pattern = Pattern.compile(identifier);
+                             @NotNull final Supplier<@Nullable String> function) {
+        this.identifier = "%" + identifier + "%";
+        this.pattern = PatternUtils.compileLiteral(identifier);
         this.function = function;
     }
 
-    /**
-     * Get the value of the placeholder.
-     *
-     * @return The value.
-     */
-    @NotNull
-    public String getValue() {
+    @Override
+    public @Nullable String getValue(@NotNull final String args,
+                                     @NotNull final PlaceholderContext context) {
         return function.get();
     }
 
+    /**
+     * Get the value of the arguments.
+     *
+     * @return The value.
+     * @deprecated Use {@link #getValue(String, PlaceholderContext)} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @NotNull
+    public String getValue() {
+        return Objects.requireNonNullElse(
+                function.get(),
+                ""
+        );
+    }
+
     @Override
-    public @NotNull String getIdentifier() {
-        return this.identifier;
+    public String tryTranslateQuickly(@NotNull final String text,
+                                      @NotNull final PlaceholderContext context) {
+        return StringUtils.replaceQuickly(
+                text,
+                this.identifier,
+                Objects.requireNonNullElse(this.getValue(this.identifier, context), "")
+        );
     }
 
     @NotNull
@@ -68,11 +87,11 @@ public final class StaticPlaceholder implements InjectablePlaceholder {
         if (!(o instanceof StaticPlaceholder that)) {
             return false;
         }
-        return Objects.equals(this.getIdentifier(), that.getIdentifier());
+        return Objects.equals(this.getPattern(), that.getPattern());
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(this.getIdentifier());
+        return Objects.hash(this.getPattern());
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/context/MergedInjectableContext.java

@@ -0,0 +1,92 @@
+package com.willfp.eco.core.placeholder.context;
+
+import com.willfp.eco.core.placeholder.InjectablePlaceholder;
+import com.willfp.eco.core.placeholder.PlaceholderInjectable;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Objects;
+import java.util.Set;
+
+/**
+ * A merged injectable context.
+ */
+public class MergedInjectableContext implements PlaceholderInjectable {
+    /**
+     * The base context.
+     */
+    private final PlaceholderInjectable baseContext;
+
+    /**
+     * The additional context.
+     */
+    private final PlaceholderInjectable additionalContext;
+
+    /**
+     * Extra injections.
+     */
+    private final Set<InjectablePlaceholder> extraInjections = new HashSet<>();
+
+    /**
+     * Create a new merged injectable context.
+     *
+     * @param baseContext       The base context.
+     * @param additionalContext The additional context.
+     */
+    public MergedInjectableContext(@NotNull final PlaceholderInjectable baseContext,
+                                   @NotNull final PlaceholderInjectable additionalContext) {
+        this.baseContext = baseContext;
+        this.additionalContext = additionalContext;
+    }
+
+    @Override
+    public void addInjectablePlaceholder(@NotNull final Iterable<InjectablePlaceholder> placeholders) {
+        for (InjectablePlaceholder placeholder : placeholders) {
+            extraInjections.add(placeholder);
+        }
+    }
+
+    @Override
+    public void clearInjectedPlaceholders() {
+        baseContext.clearInjectedPlaceholders();
+        additionalContext.clearInjectedPlaceholders();
+        extraInjections.clear();
+    }
+
+    @Override
+    public @NotNull List<InjectablePlaceholder> getPlaceholderInjections() {
+        List<InjectablePlaceholder> base = baseContext.getPlaceholderInjections();
+        List<InjectablePlaceholder> additional = additionalContext.getPlaceholderInjections();
+
+        List<InjectablePlaceholder> injections = new ArrayList<>(base.size() + additional.size() + extraInjections.size());
+
+        injections.addAll(base);
+        injections.addAll(additional);
+        injections.addAll(extraInjections);
+
+        return injections;
+    }
+
+    @Override
+    public boolean equals(@Nullable final Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (!(o instanceof MergedInjectableContext that)) {
+            return false;
+        }
+
+        return Objects.equals(baseContext, that.baseContext)
+                && Objects.equals(additionalContext, that.additionalContext)
+                && Objects.equals(extraInjections, that.extraInjections);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(baseContext, additionalContext, extraInjections);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/placeholder/context/PlaceholderContext.java

@@ -0,0 +1,252 @@
+package com.willfp.eco.core.placeholder.context;
+
+import com.willfp.eco.core.placeholder.AdditionalPlayer;
+import com.willfp.eco.core.placeholder.InjectablePlaceholder;
+import com.willfp.eco.core.placeholder.PlaceholderInjectable;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * Represents a context to translate placeholders in.
+ */
+public class PlaceholderContext {
+    /**
+     * An empty injectable.
+     */
+    private static final PlaceholderInjectable EMPTY_INJECTABLE = new PlaceholderInjectable() {
+        @Override
+        public void addInjectablePlaceholder(@NotNull final Iterable<InjectablePlaceholder> placeholders) {
+            // Do nothing.
+        }
+
+        @Override
+        public void clearInjectedPlaceholders() {
+            // Do nothing.
+        }
+
+        @Override
+        public @NotNull List<InjectablePlaceholder> getPlaceholderInjections() {
+            return Collections.emptyList();
+        }
+    };
+
+    /**
+     * An empty context.
+     */
+    public static final PlaceholderContext EMPTY = new PlaceholderContext(
+            null,
+            null,
+            null,
+            Collections.emptyList()
+    );
+
+    /**
+     * The player.
+     */
+    @Nullable
+    private final Player player;
+
+    /**
+     * The ItemStack.
+     */
+    @Nullable
+    private final ItemStack itemStack;
+
+    /**
+     * The PlaceholderInjectable context.
+     */
+    @NotNull
+    private final PlaceholderInjectable injectableContext;
+
+    /**
+     * The additional players.
+     */
+    @NotNull
+    private final Collection<AdditionalPlayer> additionalPlayers;
+
+    /**
+     * Create an empty PlaceholderContext.
+     */
+    public PlaceholderContext() {
+        this(null, null, null, Collections.emptyList());
+    }
+
+    /**
+     * Create a PlaceholderContext for a player.
+     *
+     * @param player The player.
+     */
+    public PlaceholderContext(@Nullable final Player player) {
+        this(player, null, null, Collections.emptyList());
+    }
+
+    /**
+     * Constructs a new PlaceholderContext with the given parameters.
+     *
+     * @param player            The player.
+     * @param itemStack         The ItemStack.
+     * @param injectableContext The PlaceholderInjectable parseContext.
+     * @param additionalPlayers The additional players.
+     */
+    public PlaceholderContext(@Nullable final Player player,
+                              @Nullable final ItemStack itemStack,
+                              @Nullable final PlaceholderInjectable injectableContext,
+                              @NotNull final Collection<AdditionalPlayer> additionalPlayers) {
+        this.player = player;
+        this.itemStack = itemStack;
+        this.injectableContext = Objects.requireNonNullElse(injectableContext, EMPTY_INJECTABLE);
+        this.additionalPlayers = additionalPlayers;
+    }
+
+    /**
+     * Get the player.
+     *
+     * @return The player.
+     */
+    @Nullable
+    public Player getPlayer() {
+        return player;
+    }
+
+    /**
+     * Get the ItemStack.
+     *
+     * @return The ItemStack.
+     */
+    @Nullable
+    public ItemStack getItemStack() {
+        return itemStack;
+    }
+
+    /**
+     * Get the PlaceholderInjectable context.
+     *
+     * @return The PlaceholderInjectable context.
+     */
+    @NotNull
+    public PlaceholderInjectable getInjectableContext() {
+        return injectableContext;
+    }
+
+    /**
+     * Get the additional players.
+     *
+     * @return The additional players.
+     */
+    @NotNull
+    public Collection<AdditionalPlayer> getAdditionalPlayers() {
+        return additionalPlayers;
+    }
+
+    /**
+     * Convert to a {@link com.willfp.eco.core.math.MathContext}.
+     *
+     * @return The math context.
+     * @deprecated MathContext is deprecated, use {@link PlaceholderContext} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @SuppressWarnings({"removal", "DeprecatedIsStillUsed"})
+    public com.willfp.eco.core.math.MathContext toMathContext() {
+        return new com.willfp.eco.core.math.MathContext(this.getInjectableContext(), this.getPlayer(), this.getAdditionalPlayers());
+    }
+
+    /**
+     * Copy with a player.
+     *
+     * @param player The player.
+     * @return The new context.
+     */
+    public PlaceholderContext copyWithPlayer(@Nullable final Player player) {
+        return new PlaceholderContext(
+                player,
+                this.getItemStack(),
+                this.getInjectableContext(),
+                this.getAdditionalPlayers()
+        );
+    }
+
+    /**
+     * Copy with an item.
+     *
+     * @param itemStack The ItemStack.
+     * @return The new context.
+     */
+    public PlaceholderContext copyWithItem(@Nullable final ItemStack itemStack) {
+        return new PlaceholderContext(
+                this.getPlayer(),
+                itemStack,
+                this.getInjectableContext(),
+                this.getAdditionalPlayers()
+        );
+    }
+
+    /**
+     * Copy with an extra injectable context.
+     *
+     * @param injectableContext The injectable context to add.
+     * @return The new context.
+     */
+    public PlaceholderContext withInjectableContext(@NotNull final PlaceholderInjectable injectableContext) {
+        return new PlaceholderContext(
+                this.getPlayer(),
+                this.getItemStack(),
+                new MergedInjectableContext(this.getInjectableContext(), injectableContext),
+                this.getAdditionalPlayers()
+        );
+    }
+
+    @Override
+    public String toString() {
+        return "PlaceholderContext{" +
+                "player=" + player +
+                ", itemStack=" + itemStack +
+                ", injectableContext=" + injectableContext +
+                ", additionalPlayers=" + additionalPlayers +
+                '}';
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (!(o instanceof PlaceholderContext that)) {
+            return false;
+        }
+
+        return Objects.equals(
+                getPlayer(), that.getPlayer())
+                && Objects.equals(getItemStack(), that.getItemStack())
+                && getInjectableContext().equals(that.getInjectableContext())
+                && getAdditionalPlayers().equals(that.getAdditionalPlayers()
+        );
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(getPlayer(), getItemStack(), getInjectableContext(), getAdditionalPlayers());
+    }
+
+    /**
+     * Create PlaceholderContext of a PlaceholderInjectable parseContext.
+     *
+     * @param injectableContext The PlaceholderInjectable parseContext.
+     * @return The context.
+     */
+    public static PlaceholderContext of(@NotNull final PlaceholderInjectable injectableContext) {
+        return new PlaceholderContext(
+                null,
+                null,
+                injectableContext,
+                Collections.emptyList()
+        );
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/placeholder/context/PlaceholderContextSupplier.java

@@ -0,0 +1,19 @@
+package com.willfp.eco.core.placeholder.context;
+
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * A supplier that takes a {@link PlaceholderContext} and returns a value.
+ *
+ * @param <T> The type of value to return.
+ */
+public interface PlaceholderContextSupplier<T> {
+    /**
+     * Get the value.
+     *
+     * @param context The context.
+     * @return The value.
+     */
+    @NotNull
+    T get(@NotNull PlaceholderContext context);
+}

eco-api/src/main/java/com/willfp/eco/core/placeholder/templates/DynamicInjectablePlaceholder.java

@@ -0,0 +1,57 @@
+package com.willfp.eco.core.placeholder.templates;
+
+import com.willfp.eco.core.placeholder.InjectablePlaceholder;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Objects;
+import java.util.regex.Pattern;
+
+/**
+ * A template class for dynamic placeholders.
+ */
+public abstract class DynamicInjectablePlaceholder implements InjectablePlaceholder {
+
+    /**
+     * The placeholder pattern.
+     */
+    private final Pattern pattern;
+
+    /**
+     * Create a new dynamic injectable placeholder.
+     *
+     * @param pattern The pattern.
+     */
+    protected DynamicInjectablePlaceholder(@NotNull final Pattern pattern) {
+        this.pattern = pattern;
+    }
+
+    @Override
+    public @NotNull Pattern getPattern() {
+        return pattern;
+    }
+
+    @Override
+    public String toString() {
+        return "DynamicInjectablePlaceholder{" +
+                "pattern='" + pattern + '\'' +
+                '}';
+    }
+
+    @Override
+    public boolean equals(@NotNull final Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (!(o instanceof DynamicInjectablePlaceholder that)) {
+            return false;
+        }
+
+        return Objects.equals(pattern, that.getPattern());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(pattern);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/placeholder/templates/DynamicPlaceholder.java

@@ -0,0 +1,73 @@
+package com.willfp.eco.core.placeholder.templates;
+
+import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.placeholder.RegistrablePlaceholder;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Objects;
+import java.util.regex.Pattern;
+
+/**
+ * A template class for dynamic placeholders.
+ */
+public abstract class DynamicPlaceholder implements RegistrablePlaceholder {
+    /**
+     * The plugin.
+     */
+    private final EcoPlugin plugin;
+
+    /**
+     * The placeholder pattern.
+     */
+    private final Pattern pattern;
+
+    /**
+     * Create a new dynamic placeholder.
+     *
+     * @param plugin  The plugin.
+     * @param pattern The pattern.
+     */
+    protected DynamicPlaceholder(@NotNull final EcoPlugin plugin,
+                                 @NotNull final Pattern pattern) {
+        this.plugin = plugin;
+        this.pattern = pattern;
+    }
+
+    @Override
+    public @NotNull Pattern getPattern() {
+        return pattern;
+    }
+
+    @NotNull
+    @Override
+    public EcoPlugin getPlugin() {
+        return plugin;
+    }
+
+    @Override
+    public String toString() {
+        return "DynamicPlaceholder{" +
+                "plugin='" + plugin + '\'' +
+                "pattern='" + pattern + '\'' +
+                '}';
+    }
+
+    @Override
+    public boolean equals(@NotNull final Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (!(o instanceof DynamicPlaceholder that)) {
+            return false;
+        }
+
+        return Objects.equals(pattern, that.getPattern())
+                && Objects.equals(plugin, that.getPlugin());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(pattern, plugin);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/placeholder/templates/SimpleInjectablePlaceholder.java

@@ -0,0 +1,73 @@
+package com.willfp.eco.core.placeholder.templates;
+
+import com.willfp.eco.core.placeholder.InjectablePlaceholder;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Objects;
+import java.util.regex.Pattern;
+
+/**
+ * A template class for simple placeholders.
+ */
+public abstract class SimpleInjectablePlaceholder implements InjectablePlaceholder {
+    /**
+     * The name of the placeholder.
+     */
+    private final String identifier;
+
+    /**
+     * The placeholder pattern.
+     */
+    private final Pattern pattern;
+
+    /**
+     * Create a new simple injectable placeholder.
+     *
+     * @param identifier The identifier.
+     */
+    protected SimpleInjectablePlaceholder(@NotNull final String identifier) {
+        this.identifier = identifier;
+        this.pattern = PatternUtils.compileLiteral(identifier);
+    }
+
+    @Override
+    public String tryTranslateQuickly(@NotNull final String text,
+                                      @NotNull final PlaceholderContext context) {
+        return text.replace(
+                "%" + this.identifier + "%",
+                Objects.requireNonNullElse(this.getValue(this.identifier, context), "")
+        );
+    }
+
+    @Override
+    public @NotNull Pattern getPattern() {
+        return pattern;
+    }
+
+    @Override
+    public String toString() {
+        return "SimpleInjectablePlaceholder{" +
+                "identifier='" + identifier + '\'' +
+                '}';
+    }
+
+    @Override
+    public boolean equals(@NotNull final Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (!(o instanceof SimpleInjectablePlaceholder that)) {
+            return false;
+        }
+
+        return Objects.equals(identifier, that.identifier);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(identifier);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/placeholder/templates/SimplePlaceholder.java

@@ -0,0 +1,90 @@
+package com.willfp.eco.core.placeholder.templates;
+
+import com.willfp.eco.core.EcoPlugin;
+import com.willfp.eco.core.placeholder.RegistrablePlaceholder;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Objects;
+import java.util.regex.Pattern;
+
+/**
+ * A template class for simple placeholders.
+ */
+public abstract class SimplePlaceholder implements RegistrablePlaceholder {
+    /**
+     * The plugin.
+     */
+    private final EcoPlugin plugin;
+
+    /**
+     * The name of the placeholder.
+     */
+    private final String identifier;
+
+    /**
+     * The placeholder pattern.
+     */
+    private final Pattern pattern;
+
+    /**
+     * Create a new simple placeholder.
+     *
+     * @param plugin     The plugin.
+     * @param identifier The identifier.
+     */
+    protected SimplePlaceholder(@NotNull final EcoPlugin plugin,
+                                @NotNull final String identifier) {
+        this.plugin = plugin;
+        this.identifier = identifier;
+        this.pattern = PatternUtils.compileLiteral(identifier);
+    }
+
+    @Override
+    public String tryTranslateQuickly(@NotNull final String text,
+                                      @NotNull final PlaceholderContext context) {
+        return text.replace(
+                "%" + this.identifier + "%",
+                Objects.requireNonNullElse(this.getValue(this.identifier, context), "")
+        );
+    }
+
+    @Override
+    public @NotNull Pattern getPattern() {
+        return pattern;
+    }
+
+    @NotNull
+    @Override
+    public EcoPlugin getPlugin() {
+        return plugin;
+    }
+
+    @Override
+    public String toString() {
+        return "SimplePlaceholder{" +
+                "plugin='" + plugin + '\'' +
+                "identifier='" + identifier + '\'' +
+                '}';
+    }
+
+    @Override
+    public boolean equals(@NotNull final Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (!(o instanceof SimplePlaceholder that)) {
+            return false;
+        }
+
+        return Objects.equals(pattern, that.getPattern())
+                && Objects.equals(plugin, that.getPlugin());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(identifier, plugin);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/price/ConfiguredPrice.java

@@ -1,7 +1,8 @@
 package com.willfp.eco.core.price;
 
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.config.interfaces.Config;
-import com.willfp.eco.core.math.MathContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import com.willfp.eco.core.price.impl.PriceFree;
 import com.willfp.eco.core.serialization.ConfigDeserializer;
 import com.willfp.eco.util.NumberUtils;
@@ -119,8 +120,12 @@ public final class ConfiguredPrice implements Price {
      */
     public String getDisplay(@NotNull final Player player,
                              final double multiplier) {
+        double value = this.getPrice().getValue(player, multiplier);
+
         return StringUtils.format(
-                formatString.replace("%value%", NumberUtils.format(this.getPrice().getValue(player, multiplier))),
+                formatString
+                        .replace("%value%", NumberUtils.format(value))
+                        .replace("%value_commas%", NumberUtils.formatWithCommas(value)),
                 player,
                 StringUtils.FormatOption.WITH_PLACEHOLDERS
         );
@@ -158,17 +163,32 @@ public final class ConfiguredPrice implements Price {
             if (!(
                     config.has("value")
                             && config.has("type")
-                            && config.has("display")
             )) {
                 return null;
             }
 
-            String formatString = config.getString("display");
+            String formatString;
+
+            String langConfig = Eco.get().getEcoPlugin().getLangYml()
+                    .getSubsections("price-display")
+                    .stream()
+                    .filter(section -> section.getString("type").equalsIgnoreCase(config.getString("type")))
+                    .findFirst()
+                    .map(section -> section.getString("display"))
+                    .orElse(null);
+
+            if (langConfig != null) {
+                formatString = langConfig;
+            } else if (config.has("display")) {
+                formatString = config.getString("display");
+            } else {
+                return null;
+            }
 
             Price price = Prices.create(
                     config.getString("value"),
                     config.getString("type"),
-                    MathContext.of(config)
+                    PlaceholderContext.of(config)
             );
 
             return new ConfiguredPrice(price, formatString);

eco-api/src/main/java/com/willfp/eco/core/price/PriceFactory.java

@@ -1,6 +1,7 @@
 package com.willfp.eco.core.price;
 
-import com.willfp.eco.core.math.MathContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContextSupplier;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 
@@ -10,7 +11,8 @@ import java.util.function.Function;
 /**
  * Create prices.
  * <p>
- * You must override one of the create methods.
+ * Override create(PlaceholderContext, PlaceholderContextSupplier), other methods
+ * are for backwards compatibility.
  */
 public interface PriceFactory {
     /**
@@ -27,20 +29,38 @@ public interface PriceFactory {
      *
      * @param value The value.
      * @return The price.
+     * @deprecated Use {@link #create(PlaceholderContext, PlaceholderContextSupplier)} instead.
      */
+    @Deprecated(since = "6.56.0", forRemoval = true)
     default @NotNull Price create(final double value) {
-        return create(MathContext.EMPTY, (ctx) -> value);
+        return create(PlaceholderContext.EMPTY, (ctx) -> value);
     }
 
     /**
      * Create the price.
      *
      * @param baseContext The base MathContext.
-     * @param function    The function to use. Should use {@link MathContext#copyWithPlayer(MathContext, Player)} on calls.
+     * @param function    The function to use. Should use {@link com.willfp.eco.core.math.MathContext#copyWithPlayer(com.willfp.eco.core.math.MathContext, Player)} on calls.
+     * @return The price.
+     * @deprecated Use {@link #create(PlaceholderContext, PlaceholderContextSupplier)} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @SuppressWarnings("removal")
+    default @NotNull Price create(@NotNull final com.willfp.eco.core.math.MathContext baseContext,
+                                  @NotNull final Function<com.willfp.eco.core.math.MathContext, Double> function) {
+        return create(baseContext.toPlaceholderContext(), (PlaceholderContext ctx) -> function.apply(ctx.toMathContext()));
+    }
+
+    /**
+     * Create the price.
+     *
+     * @param baseContext The base PlaceholderContext.
+     * @param function    The function to use. Should use {@link PlaceholderContext#copyWithPlayer(Player)} on calls.
      * @return The price.
      */
-    default @NotNull Price create(@NotNull final MathContext baseContext,
-                                  @NotNull final Function<MathContext, Double> function) {
-        return create(function.apply(baseContext));
+    @SuppressWarnings("removal")
+    default @NotNull Price create(@NotNull final PlaceholderContext baseContext,
+                                  @NotNull final PlaceholderContextSupplier<Double> function) {
+        return create(baseContext.toMathContext(), (com.willfp.eco.core.math.MathContext ctx) -> function.get(ctx.toPlaceholderContext()));
     }
 }

eco-api/src/main/java/com/willfp/eco/core/price/Prices.java

@@ -2,7 +2,8 @@ package com.willfp.eco.core.price;
 
 import com.willfp.eco.core.items.Items;
 import com.willfp.eco.core.items.TestableItem;
-import com.willfp.eco.core.math.MathContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContextSupplier;
 import com.willfp.eco.core.price.impl.PriceEconomy;
 import com.willfp.eco.core.price.impl.PriceFree;
 import com.willfp.eco.core.price.impl.PriceItem;
@@ -13,7 +14,6 @@ import org.jetbrains.annotations.Nullable;
 
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
-import java.util.function.Function;
 
 /**
  * Class to manage prices.
@@ -48,7 +48,28 @@ public final class Prices {
     @NotNull
     public static Price create(@NotNull final String expression,
                                @Nullable final String priceName) {
-        return create(expression, priceName, MathContext.EMPTY);
+        return create(expression, priceName, PlaceholderContext.EMPTY);
+    }
+
+    /**
+     * Create price from an expression (representing the value),
+     * and a price name. Uses a context to parse the expression.
+     * <p>
+     * Supports items as price names.
+     *
+     * @param expression The expression for the value.
+     * @param priceName  The price name.
+     * @param context    The math context to parse the expression.
+     * @return The price, or free if invalid.
+     * @deprecated Use {@link #create(String, String, PlaceholderContext)} instead.
+     */
+    @NotNull
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @SuppressWarnings("removal")
+    public static Price create(@NotNull final String expression,
+                               @Nullable final String priceName,
+                               @NotNull final com.willfp.eco.core.math.MathContext context) {
+        return create(expression, priceName, context.toPlaceholderContext());
     }
 
     /**
@@ -65,8 +86,8 @@ public final class Prices {
     @NotNull
     public static Price create(@NotNull final String expression,
                                @Nullable final String priceName,
-                               @NotNull final MathContext context) {
-        Function<MathContext, Double> function = (ctx) -> NumberUtils.evaluateExpression(
+                               @NotNull final PlaceholderContext context) {
+        PlaceholderContextSupplier<Double> function = (ctx) -> NumberUtils.evaluateExpression(
                 expression,
                 ctx
         );

eco-api/src/main/java/com/willfp/eco/core/price/impl/PriceEconomy.java

@@ -1,7 +1,8 @@
 package com.willfp.eco.core.price.impl;
 
 import com.willfp.eco.core.integrations.economy.EconomyManager;
-import com.willfp.eco.core.math.MathContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContextSupplier;
 import com.willfp.eco.core.price.Price;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
@@ -18,12 +19,12 @@ public final class PriceEconomy implements Price {
     /**
      * The value of the price.
      */
-    private final Function<MathContext, Double> function;
+    private final PlaceholderContextSupplier<Double> function;
 
     /**
-     * The base math context.
+     * The base placeholder context.
      */
-    private final MathContext baseContext;
+    private final PlaceholderContext baseContext;
 
     /**
      * The multipliers.
@@ -36,7 +37,21 @@ public final class PriceEconomy implements Price {
      * @param value The value.
      */
     public PriceEconomy(final double value) {
-        this(MathContext.EMPTY, ctx -> value);
+        this(PlaceholderContext.EMPTY, (PlaceholderContext ctx) -> value);
+    }
+
+    /**
+     * Create a new economy-based price.
+     *
+     * @param baseContext The base context.
+     * @param function    The function.
+     * @deprecated Use {@link #PriceEconomy(PlaceholderContext, PlaceholderContextSupplier)} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @SuppressWarnings("removal")
+    public PriceEconomy(@NotNull final com.willfp.eco.core.math.MathContext baseContext,
+                        @NotNull final Function<com.willfp.eco.core.math.MathContext, Double> function) {
+        this(baseContext.toPlaceholderContext(), (PlaceholderContext ctx) -> function.apply(ctx.toMathContext()));
     }
 
     /**
@@ -45,8 +60,8 @@ public final class PriceEconomy implements Price {
      * @param baseContext The base context.
      * @param function    The function.
      */
-    public PriceEconomy(@NotNull final MathContext baseContext,
-                        @NotNull final Function<MathContext, Double> function) {
+    public PriceEconomy(@NotNull final PlaceholderContext baseContext,
+                        @NotNull final PlaceholderContextSupplier<Double> function) {
         this.baseContext = baseContext;
         this.function = function;
     }
@@ -72,7 +87,7 @@ public final class PriceEconomy implements Price {
     @Override
     public double getValue(@NotNull final Player player,
                            final double multiplier) {
-        return this.function.apply(MathContext.copyWithPlayer(baseContext, player)) * getMultiplier(player) * multiplier;
+        return this.function.get(baseContext.copyWithPlayer(player)) * getMultiplier(player) * multiplier;
     }
 
     @Override

eco-api/src/main/java/com/willfp/eco/core/price/impl/PriceItem.java

@@ -3,7 +3,8 @@ package com.willfp.eco.core.price.impl;
 import com.willfp.eco.core.drops.DropQueue;
 import com.willfp.eco.core.items.HashedItem;
 import com.willfp.eco.core.items.TestableItem;
-import com.willfp.eco.core.math.MathContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.core.placeholder.context.PlaceholderContextSupplier;
 import com.willfp.eco.core.price.Price;
 import org.bukkit.Material;
 import org.bukkit.entity.Player;
@@ -20,14 +21,14 @@ import java.util.function.Function;
  */
 public final class PriceItem implements Price {
     /**
-     * The base MathContext.
+     * The base PlaceholderContext.
      */
-    private final MathContext baseContext;
+    private final PlaceholderContext baseContext;
 
     /**
      * The amount of items.
      */
-    private final Function<MathContext, Double> function;
+    private final PlaceholderContextSupplier<Double> function;
 
     /**
      * The item.
@@ -47,7 +48,23 @@ public final class PriceItem implements Price {
      */
     public PriceItem(final int amount,
                      @NotNull final TestableItem item) {
-        this(MathContext.EMPTY, ctx -> (double) amount, item);
+        this(PlaceholderContext.EMPTY, (PlaceholderContext ctx) -> (double) amount, item);
+    }
+
+    /**
+     * Create a new item-based price.
+     *
+     * @param baseContext The base MathContext.
+     * @param function    The function to get the amount of items to remove.
+     * @param item        The item.
+     * @deprecated Use {@link #PriceItem(PlaceholderContext, PlaceholderContextSupplier, TestableItem)} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @SuppressWarnings("removal")
+    public PriceItem(@NotNull final com.willfp.eco.core.math.MathContext baseContext,
+                     @NotNull final Function<com.willfp.eco.core.math.MathContext, Double> function,
+                     @NotNull final TestableItem item) {
+        this(baseContext.toPlaceholderContext(), (PlaceholderContext ctx) -> function.apply(ctx.toMathContext()), item);
     }
 
     /**
@@ -57,8 +74,8 @@ public final class PriceItem implements Price {
      * @param function    The function to get the amount of items to remove.
      * @param item        The item.
      */
-    public PriceItem(@NotNull final MathContext baseContext,
-                     @NotNull final Function<MathContext, Double> function,
+    public PriceItem(@NotNull final PlaceholderContext baseContext,
+                     @NotNull final PlaceholderContextSupplier<Double> function,
                      @NotNull final TestableItem item) {
         this.baseContext = baseContext;
         this.function = function;
@@ -137,7 +154,7 @@ public final class PriceItem implements Price {
     public double getValue(@NotNull final Player player,
                            final double multiplier) {
         return Math.toIntExact(Math.round(
-                this.function.apply(MathContext.copyWithPlayer(baseContext, player))
+                this.function.get(baseContext.copyWithPlayer(player))
                         * getMultiplier(player) * multiplier
         ));
     }

eco-api/src/main/java/com/willfp/eco/core/proxy/ProxyConstants.java

@@ -1,5 +1,6 @@
 package com.willfp.eco.core.proxy;
 
+import com.willfp.eco.core.version.Version;
 import org.bukkit.Bukkit;
 
 import java.util.Arrays;
@@ -12,7 +13,7 @@ public final class ProxyConstants {
     /**
      * The NMS version that the server is running on.
      */
-    public static final String NMS_VERSION = Bukkit.getServer().getClass().getPackage().getName().split("\\.")[3];
+    public static final String NMS_VERSION;
 
     /**
      * All supported NMS versions.
@@ -23,10 +24,27 @@ public final class ProxyConstants {
             "v1_18_R2",
             "v1_19_R1",
             "v1_19_R2",
-            "v1_19_R3"
+            "v1_19_R3",
+            "v1_20_R1",
+            "v1_20_R2",
+            "v1_20_R3",
+            "v1_21"
     );
 
     private ProxyConstants() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }
+
+    static {
+        String currentMinecraftVersion = Bukkit.getServer().getBukkitVersion().split("-")[0];
+        String nmsVersion;
+
+        if (new Version(currentMinecraftVersion).compareTo(new Version("1.20.5")) < 0) {
+            nmsVersion = Bukkit.getServer().getClass().getPackage().getName().split("\\.")[3];
+        } else {
+            nmsVersion = "v" + currentMinecraftVersion.replace(".", "_");
+        }
+
+        NMS_VERSION = nmsVersion;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/recipe/Recipes.java

@@ -9,7 +9,6 @@ import com.willfp.eco.core.items.Items;
 import com.willfp.eco.core.recipe.recipes.CraftingRecipe;
 import com.willfp.eco.core.recipe.recipes.ShapedCraftingRecipe;
 import com.willfp.eco.util.NamespacedKeyUtils;
-import org.bukkit.Bukkit;
 import org.bukkit.NamespacedKey;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -127,8 +126,8 @@ public final class Recipes {
         }
 
         if (builder.isAir()) {
-            Bukkit.getLogger().warning("RECIPE ERROR! " + plugin.getName() + ":" + key + " consists only");
-            Bukkit.getLogger().warning("of air or invalid items! Please change that or disable this recipe.");
+            plugin.getLogger().warning("Crafting recipe " + plugin.getID() + ":" + key + " consists only");
+            plugin.getLogger().warning("of air or invalid items! It will not be registered.");
             return null;
         }
 

eco-api/src/main/java/com/willfp/eco/core/registry/Registry.java

@@ -62,6 +62,7 @@ public class Registry<T extends Registrable> implements Iterable<T> {
         registry.put(element.getID(), element);
 
         element.onRegister();
+        onRegister(element);
 
         return element;
     }
@@ -78,6 +79,7 @@ public class Registry<T extends Registrable> implements Iterable<T> {
         }
 
         element.onRemove();
+        onRemove(element);
 
         registry.remove(element.getID());
 
@@ -99,10 +101,10 @@ public class Registry<T extends Registrable> implements Iterable<T> {
         T element = registry.get(id);
 
         if (element != null) {
-            element.onRemove();
+            return remove(element);
         }
 
-        return registry.remove(id);
+        return null;
     }
 
     /**
@@ -149,6 +151,10 @@ public class Registry<T extends Registrable> implements Iterable<T> {
      * @param locker The locker.
      */
     public void lock(@Nullable final Object locker) {
+        if (this.isLocked && this.locker != locker) {
+            throw new IllegalArgumentException("Registry is already locked with a different locker!");
+        }
+
         this.locker = locker;
         isLocked = true;
     }
@@ -162,9 +168,29 @@ public class Registry<T extends Registrable> implements Iterable<T> {
         if (this.locker != locker) {
             throw new IllegalArgumentException("Cannot unlock registry!");
         }
+
+        this.locker = null;
         isLocked = false;
     }
 
+    /**
+     * Run when an element is registered.
+     *
+     * @param element The element.
+     */
+    protected void onRegister(@NotNull final T element) {
+        // Override this method to do something when an element is registered.
+    }
+
+    /**
+     * Run when an element is removed.
+     *
+     * @param element The element.
+     */
+    protected void onRemove(@NotNull final T element) {
+        // Override this method to do something when an element is removed.
+    }
+
     /**
      * Get if the registry is empty.
      *

eco-api/src/main/java/com/willfp/eco/core/web/UpdateChecker.java

@@ -1,13 +1,13 @@
 package com.willfp.eco.core.web;
 
 import com.willfp.eco.core.EcoPlugin;
-import org.bukkit.util.Consumer;
 import org.jetbrains.annotations.NotNull;
 
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;
 import java.util.Scanner;
+import java.util.function.Consumer;
 
 /**
  * Class to check for updates of a plugin on spigot.

eco-api/src/main/java/com/willfp/eco/util/DurabilityUtils.java

@@ -158,11 +158,8 @@ public final class DurabilityUtils {
         }
 
         if (item.getItemMeta() instanceof Damageable meta) {
-            meta.setDamage(meta.getDamage() - repair);
+            meta.setDamage(Math.max(0, meta.getDamage() - repair));
 
-            if (meta.getDamage() < 0) {
-                meta.setDamage(0);
-            }
             item.setItemMeta((ItemMeta) meta);
         }
     }

eco-api/src/main/java/com/willfp/eco/util/EntityUtils.java

@@ -0,0 +1,31 @@
+package com.willfp.eco.util;
+
+import com.willfp.eco.core.Eco;
+import net.kyori.adventure.text.Component;
+import org.bukkit.entity.LivingEntity;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Utilities / API methods for entities.
+ */
+public final class EntityUtils {
+    /**
+     * Set a client-side entity display name.
+     *
+     * @param entity  The entity.
+     * @param player  The player.
+     * @param name    The display name.
+     * @param visible If the display name should be forcibly visible.
+     */
+    public static void setClientsideDisplayName(@NotNull final LivingEntity entity,
+                                                @NotNull final Player player,
+                                                @NotNull final Component name,
+                                                final boolean visible) {
+        Eco.get().setClientsideDisplayName(entity, player, name, visible);
+    }
+
+    private EntityUtils() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

eco-api/src/main/java/com/willfp/eco/util/NumberUtils.java

@@ -1,10 +1,9 @@
 package com.willfp.eco.util;
 
 import com.willfp.eco.core.Eco;
-import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
-import com.willfp.eco.core.math.MathContext;
 import com.willfp.eco.core.placeholder.AdditionalPlayer;
 import com.willfp.eco.core.placeholder.PlaceholderInjectable;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -13,6 +12,7 @@ import java.text.DecimalFormat;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Map;
+import java.util.Objects;
 import java.util.TreeMap;
 import java.util.concurrent.ThreadLocalRandom;
 
@@ -203,6 +203,20 @@ public final class NumberUtils {
         return formatted.endsWith("00") ? String.valueOf((int) toFormat) : formatted;
     }
 
+    /**
+     * Format double to string with commas.
+     *
+     * @param toFormat The number to format.
+     * @return Formatted.
+     */
+    @NotNull
+    public static String formatWithCommas(final double toFormat) {
+        DecimalFormat df = new DecimalFormat("#,##0.00");
+        String formatted = df.format(toFormat);
+
+        return formatted.endsWith(".00") ? formatted.substring(0, formatted.length() - 3) : formatted;
+    }
+
     /**
      * Evaluate an expression.
      *
@@ -210,7 +224,7 @@ public final class NumberUtils {
      * @return The value of the expression, or zero if invalid.
      */
     public static double evaluateExpression(@NotNull final String expression) {
-        return evaluateExpression(expression, MathContext.EMPTY);
+        return evaluateExpression(expression, PlaceholderContext.EMPTY);
     }
 
     /**
@@ -222,7 +236,7 @@ public final class NumberUtils {
      */
     public static double evaluateExpression(@NotNull final String expression,
                                             @Nullable final Player player) {
-        return evaluateExpression(expression, player, PlaceholderManager.EMPTY_INJECTABLE);
+        return evaluateExpression(expression, player, null);
     }
 
     /**
@@ -230,12 +244,12 @@ public final class NumberUtils {
      *
      * @param expression The expression.
      * @param player     The player.
-     * @param context    The injectable placeholders.
+     * @param context    The injectableContext placeholders.
      * @return The value of the expression, or zero if invalid.
      */
     public static double evaluateExpression(@NotNull final String expression,
                                             @Nullable final Player player,
-                                            @NotNull final PlaceholderInjectable context) {
+                                            @Nullable final PlaceholderInjectable context) {
         return evaluateExpression(expression, player, context, new ArrayList<>());
     }
 
@@ -244,30 +258,65 @@ public final class NumberUtils {
      *
      * @param expression        The expression.
      * @param player            The player.
-     * @param context           The injectable placeholders.
+     * @param context           The injectableContext placeholders.
      * @param additionalPlayers Additional players to parse placeholders for.
      * @return The value of the expression, or zero if invalid.
      */
     public static double evaluateExpression(@NotNull final String expression,
                                             @Nullable final Player player,
-                                            @NotNull final PlaceholderInjectable context,
+                                            @Nullable final PlaceholderInjectable context,
                                             @NotNull final Collection<AdditionalPlayer> additionalPlayers) {
-        return Eco.get().evaluate(expression, new MathContext(
-                context,
+        return evaluateExpression(
+                expression,
+                new PlaceholderContext(
                         player,
+                        null,
+                        context,
                         additionalPlayers
-        ));
+                )
+        );
     }
 
     /**
-     * Evaluate an expression with respect to a player (for placeholders).
+     * Evaluate an expression in a context.
      *
      * @param expression The expression.
-     * @param context    The math context.
+     * @param context    The context.
+     * @return The value of the expression, or zero if invalid.
+     * @deprecated Use {@link #evaluateExpression(String, PlaceholderContext)} instead.
+     */
+    @Deprecated(since = "6.56.0", forRemoval = true)
+    @SuppressWarnings({"removal", "DeprecatedIsStillUsed"})
+    public static double evaluateExpression(@NotNull final String expression,
+                                            @NotNull final com.willfp.eco.core.math.MathContext context) {
+        return evaluateExpression(expression, context.toPlaceholderContext());
+    }
+
+    /**
+     * Evaluate an expression in a context.
+     *
+     * @param expression The expression.
+     * @param context    The context.
      * @return The value of the expression, or zero if invalid.
      */
     public static double evaluateExpression(@NotNull final String expression,
-                                            @NotNull final MathContext context) {
+                                            @NotNull final PlaceholderContext context) {
+        return Objects.requireNonNullElse(
+                evaluateExpressionOrNull(expression, context),
+                0.0
+        );
+    }
+
+    /**
+     * Evaluate an expression in a context.
+     *
+     * @param expression The expression.
+     * @param context    The context.
+     * @return The value of the expression, or zero if invalid.
+     */
+    @Nullable
+    public static Double evaluateExpressionOrNull(@NotNull final String expression,
+                                                  @NotNull final PlaceholderContext context) {
         return Eco.get().evaluate(expression, context);
     }
 

eco-api/src/main/java/com/willfp/eco/util/PatternUtils.java

@@ -0,0 +1,36 @@
+package com.willfp.eco.util;
+
+import com.github.benmanes.caffeine.cache.Cache;
+import com.github.benmanes.caffeine.cache.Caffeine;
+import com.willfp.eco.core.Eco;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.concurrent.TimeUnit;
+import java.util.regex.Pattern;
+
+/**
+ * Utilities / API methods for patterns.
+ */
+public final class PatternUtils {
+    /**
+     * Cache of compiled literal patterns.
+     */
+    private static final Cache<String, Pattern> LITERAL_PATTERN_CACHE = Caffeine.newBuilder()
+            .expireAfterAccess(Eco.get().getEcoPlugin().getConfigYml().getInt("literal-cache-ttl"), TimeUnit.MINUTES)
+            .build();
+
+    /**
+     * Compile a literal pattern.
+     *
+     * @param pattern The pattern.
+     * @return The compiled pattern.
+     */
+    @NotNull
+    public static Pattern compileLiteral(@NotNull final String pattern) {
+        return LITERAL_PATTERN_CACHE.get(pattern, (it) -> Pattern.compile(it, Pattern.LITERAL));
+    }
+
+    private PatternUtils() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

eco-api/src/main/java/com/willfp/eco/util/PotionUtils.java

@@ -13,6 +13,7 @@ public final class PotionUtils {
      * @param data The data.
      * @return The duration.
      */
+    @SuppressWarnings("deprecation")
     public static int getDuration(@NotNull final PotionData data) {
         if (data.isExtended()) {
             return switch (data.getType()) {

eco-api/src/main/java/com/willfp/eco/util/StringUtils.java

@@ -8,7 +8,10 @@ import com.google.common.collect.ImmutableMap;
 import com.google.gson.JsonSyntaxException;
 import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
+import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.JoinConfiguration;
+import net.kyori.adventure.text.TextComponent;
 import net.kyori.adventure.text.format.TextDecoration;
 import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
 import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
@@ -200,6 +203,26 @@ public final class StringUtils {
         return translated;
     }
 
+    /**
+     * Format a list of strings.
+     * <p>
+     * Coverts color codes and placeholders.
+     *
+     * @param list    The messages to format.
+     * @param context The context.
+     * @return The message, format.
+     */
+    @NotNull
+    public static List<String> formatList(@NotNull final List<String> list,
+                                          @NotNull PlaceholderContext context) {
+        List<String> translated = new ArrayList<>();
+        for (String string : list) {
+            translated.add(format(string, context));
+        }
+
+        return translated;
+    }
+
     /**
      * Format a string.
      * <p>
@@ -242,7 +265,7 @@ public final class StringUtils {
     @NotNull
     public static String format(@NotNull final String message,
                                 @NotNull final FormatOption option) {
-        return format(message, null, option);
+        return format(message, (Player) null, option);
     }
 
     /**
@@ -287,7 +310,7 @@ public final class StringUtils {
     @NotNull
     public static Component formatToComponent(@NotNull final String message,
                                               @NotNull final FormatOption option) {
-        return formatToComponent(message, null, option);
+        return formatToComponent(message, (Player) null, option);
     }
 
     /**
@@ -321,10 +344,49 @@ public final class StringUtils {
     public static String format(@NotNull final String message,
                                 @Nullable final Player player,
                                 @NotNull final FormatOption option) {
-        String processedMessage = message;
         if (option == FormatOption.WITH_PLACEHOLDERS) {
-            processedMessage = PlaceholderManager.translatePlaceholders(processedMessage, player);
+            return format(
+                    message,
+                    new PlaceholderContext(player)
+            );
         }
+
+        return STRING_FORMAT_CACHE.get(message);
+    }
+
+    /**
+     * Format a string to a component.
+     * <p>
+     * Converts color codes and placeholders if specified.
+     *
+     * @param message The message to translate.
+     * @param context The placeholder context.
+     * @return The message, formatted, as a component.
+     * @see StringUtils#format(String, Player)
+     */
+    @NotNull
+    public static Component formatToComponent(@NotNull final String message,
+                                              @NotNull final PlaceholderContext context) {
+        return toComponent(format(message, context));
+    }
+
+    /**
+     * Format a string.
+     * <p>
+     * Coverts color codes and placeholders if specified.
+     *
+     * @param message The message to format.
+     * @param context The context to translate placeholders with respect to.
+     * @return The message, formatted.
+     */
+    @NotNull
+    public static String format(@NotNull final String message,
+                                @NotNull final PlaceholderContext context) {
+        String processedMessage = message;
+        processedMessage = PlaceholderManager.translatePlaceholders(
+                processedMessage,
+                context
+        );
         return STRING_FORMAT_CACHE.get(processedMessage);
     }
 
@@ -674,6 +736,177 @@ public final class StringUtils {
         return builder.toString();
     }
 
+    /**
+     * Fast implementation of {@link String#replace(CharSequence, CharSequence)}
+     *
+     * @param input       The input string.
+     * @param target      The target string.
+     * @param replacement The replacement string.
+     * @return The replaced string.
+     */
+    @NotNull
+    public static String replaceQuickly(@NotNull final String input,
+                                        @NotNull final String target,
+                                        @NotNull final String replacement) {
+        int targetLength = target.length();
+
+        // Count the number of original occurrences
+        int count = 0;
+        for (
+                int index = input.indexOf(target);
+                index != -1;
+                index = input.indexOf(target, index + targetLength)
+        ) {
+            count++;
+        }
+
+        if (count == 0) {
+            return input;
+        }
+
+        int replacementLength = replacement.length();
+        int inputLength = input.length();
+
+        // Pre-calculate the final size of the StringBuilder
+        int newSize = inputLength + (replacementLength - targetLength) * count;
+        StringBuilder result = new StringBuilder(newSize);
+
+        int start = 0;
+        for (
+                int index = input.indexOf(target);
+                index != -1;
+                index = input.indexOf(target, start)
+        ) {
+            result.append(input, start, index);
+            result.append(replacement);
+            start = index + targetLength;
+        }
+
+        result.append(input, start, inputLength);
+        return result.toString();
+    }
+
+    /**
+     * Line wrap a list of strings while preserving formatting.
+     *
+     * @param input      The input list.
+     * @param lineLength The length of each line.
+     * @return The wrapped list.
+     */
+    @NotNull
+    public static List<String> lineWrap(@NotNull final List<String> input,
+                                        final int lineLength) {
+        return lineWrap(input, lineLength, true);
+    }
+
+    /**
+     * Line wrap a list of strings while preserving formatting.
+     *
+     * @param input          The input list.
+     * @param lineLength     The length of each line.
+     * @param preserveMargin If the string has a margin, add it to the next line.
+     * @return The wrapped list.
+     */
+    @NotNull
+    public static List<String> lineWrap(@NotNull final List<String> input,
+                                        final int lineLength,
+                                        final boolean preserveMargin) {
+        return input.stream()
+                .flatMap(line -> lineWrap(line, lineLength, preserveMargin).stream())
+                .toList();
+    }
+
+    /**
+     * Line wrap a string while preserving formatting.
+     *
+     * @param input      The input list.
+     * @param lineLength The length of each line.
+     * @return The wrapped list.
+     */
+    @NotNull
+    public static List<String> lineWrap(@NotNull final String input,
+                                        final int lineLength) {
+        return lineWrap(input, lineLength, true);
+    }
+
+    /**
+     * Line wrap a string while preserving formatting.
+     *
+     * @param input          The input string.
+     * @param lineLength     The length of each line.
+     * @param preserveMargin If the string has a margin, add it to the start of each line.
+     * @return The wrapped string.
+     */
+    @NotNull
+    public static List<String> lineWrap(@NotNull final String input,
+                                        final int lineLength,
+                                        final boolean preserveMargin) {
+        int margin = preserveMargin ? getMargin(input) : 0;
+        TextComponent space = Component.text(" ");
+
+        Component asComponent = toComponent(input);
+
+        // The component contains the text as its children, so the child components
+        // are accessed like this:
+        List<TextComponent> children = new ArrayList<>();
+
+        if (asComponent instanceof TextComponent) {
+            children.add((TextComponent) asComponent);
+        }
+
+        for (Component child : asComponent.children()) {
+            children.add((TextComponent) child);
+        }
+
+        // Start by splitting the component into individual characters.
+        List<TextComponent> letters = new ArrayList<>();
+        for (TextComponent child : children) {
+            for (char c : child.content().toCharArray()) {
+                letters.add(Component.text(c).mergeStyle(child));
+            }
+        }
+
+        List<Component> lines = new ArrayList<>();
+        List<TextComponent> currentLine = new ArrayList<>();
+        boolean isFirstLine = true;
+
+        for (TextComponent letter : letters) {
+            if (currentLine.size() > lineLength && letter.content().isBlank()) {
+                lines.add(Component.join(JoinConfiguration.noSeparators(), currentLine));
+                currentLine.clear();
+                isFirstLine = false;
+            } else {
+                // Add margin if starting a new line.
+                if (currentLine.isEmpty() && !isFirstLine) {
+                    if (preserveMargin) {
+                        for (int i = 0; i < margin; i++) {
+                            currentLine.add(space);
+                        }
+                    }
+                }
+
+                currentLine.add(letter);
+            }
+        }
+
+        // Push last line.
+        lines.add(Component.join(JoinConfiguration.noSeparators(), currentLine));
+
+        // Convert back to legacy strings.
+        return lines.stream().map(StringUtils::toLegacy)
+                .collect(Collectors.toList());
+    }
+
+    /**
+     * Get a string's margin.
+     *
+     * @param input The input string.
+     * @return The margin.
+     */
+    public static int getMargin(@NotNull final String input) {
+        return input.indexOf(input.trim());
+    }
+
     /**
      * Options for formatting.
      */

eco-api/src/main/kotlin/com/willfp/eco/core/items/Items.kt

@@ -22,6 +22,8 @@ fun ItemMeta.mergeFrom(other: ItemMeta): ItemMeta =
  * @see Items.getBaseNBT
  * @see Items.setBaseNBT
  */
+@Suppress("DEPRECATION")
+@Deprecated("Not supported in 1.20.5+", level = DeprecationLevel.ERROR)
 var ItemStack.baseNBT: PersistentDataContainer
     get() = Items.getBaseNBT(this)
     set(value) {
@@ -29,6 +31,8 @@ var ItemStack.baseNBT: PersistentDataContainer
     }
 
 /** @see Items.setBaseNBT */
+@Suppress("DEPRECATION", "DeprecatedCallableAddReplaceWith")
+@Deprecated("Not supported in 1.20.5+", level = DeprecationLevel.ERROR)
 fun ItemStack.clearNBT() =
     Items.setBaseNBT(this, null)
 
@@ -37,9 +41,14 @@ fun ItemStack.toSNBT() =
     Items.toSNBT(this)
 
 /** @see Items.isEmpty */
+@Deprecated("Use ItemStack.isEcoEmpty", ReplaceWith("Items.isEmpty(this)"))
 val ItemStack?.isEmpty: Boolean
     get() = Items.isEmpty(this)
 
+/** @see Items.isEmpty */
+val ItemStack?.isEcoEmpty: Boolean
+    get() = Items.isEmpty(this)
+
 /** @see Items.matchesAny */
 fun Collection<TestableItem>.matches(item: ItemStack): Boolean =
     Items.matchesAny(item, this)

eco-api/src/main/kotlin/com/willfp/eco/core/map/DefaultMap.kt

@@ -8,7 +8,7 @@ package com.willfp.eco.core.map
  * @see ListMap
  */
 @Suppress("RedundantOverride")
-class MutableListMap<K : Any, V : Any> : ListMap<K, V>() {
+class MutableListMap<K : Any, V> : ListMap<K, V>() {
     /**
      * Override with enforced MutableList type.
      */
@@ -18,7 +18,7 @@ class MutableListMap<K : Any, V : Any> : ListMap<K, V>() {
     /**
      * Override with enforced MutableList type.
      */
-    override fun getOrDefault(key: K, defaultValue: MutableList<V>?): MutableList<V> {
+    override fun getOrDefault(key: K, defaultValue: MutableList<V>): MutableList<V> {
         return super.getOrDefault(key, defaultValue)
     }
 }
@@ -29,6 +29,12 @@ class MutableListMap<K : Any, V : Any> : ListMap<K, V>() {
 fun <K : Any, V : Any> defaultMap(defaultValue: V) =
     DefaultMap<K, V>(defaultValue)
 
+/**
+ * @see DefaultMap
+ */
+fun <K : Any, V : Any> defaultMap(defaultValue: () -> V) =
+    DefaultMap<K, V>(defaultValue())
+
 /**
  * @see ListMap
  */
@@ -38,11 +44,13 @@ fun <K : Any, V : Any> listMap() =
 /**
  * @see DefaultMap.createNestedMap
  */
-fun <K : Any, K1 : Any, V : Any> nestedMap() =
+fun <K : Any, K1 : Any, V> nestedMap() =
     DefaultMap.createNestedMap<K, K1, V>()
 
 /**
  * @see DefaultMap.createNestedListMap
  */
-fun <K : Any, K1 : Any, V : Any> nestedListMap() =
-    DefaultMap<K, MutableListMap<K1, V>>(MutableListMap())
+fun <K : Any, K1 : Any, V> nestedListMap() =
+    DefaultMap<K, MutableListMap<K1, V>>() {
+        MutableListMap()
+    }

eco-api/src/main/kotlin/com/willfp/eco/core/placeholder/Placeholder.kt

@@ -0,0 +1,14 @@
+@file:JvmName("PlaceholderExtensions")
+
+package com.willfp.eco.core.placeholder
+
+import com.willfp.eco.core.integrations.placeholder.PlaceholderManager
+import com.willfp.eco.core.placeholder.context.PlaceholderContext
+
+/** @see PlaceholderManager.translatePlaceholders */
+fun String.translatePlaceholders(context: PlaceholderContext) =
+    PlaceholderManager.translatePlaceholders(this, context)
+
+/** @see PlaceholderManager.findPlaceholdersIn */
+fun String.findPlaceholders(): List<String> =
+    PlaceholderManager.findPlaceholdersIn(this)

eco-api/src/main/kotlin/com/willfp/eco/core/placeholder/context/PlaceholderContext.kt

@@ -0,0 +1,25 @@
+@file:JvmName("PlaceholderContextExtensions")
+
+package com.willfp.eco.core.placeholder.context
+
+import com.willfp.eco.core.placeholder.AdditionalPlayer
+import com.willfp.eco.core.placeholder.PlaceholderInjectable
+import org.bukkit.entity.Player
+import org.bukkit.inventory.ItemStack
+
+/** @see PlaceholderContext */
+@JvmOverloads
+fun placeholderContext(
+    player: Player? = null,
+    item: ItemStack? = null,
+    injectable: PlaceholderInjectable? = null,
+    additionalPlayers: Collection<AdditionalPlayer> = emptyList()
+): PlaceholderContext = PlaceholderContext(player, item, injectable, additionalPlayers)
+
+/** @see PlaceholderContext */
+fun PlaceholderContext.copy(
+    player: Player? = this.player,
+    item: ItemStack? = this.itemStack,
+    injectable: PlaceholderInjectable? = this.injectableContext,
+    additionalPlayers: Collection<AdditionalPlayer> = this.additionalPlayers
+): PlaceholderContext = PlaceholderContext(player, item, injectable, additionalPlayers)

eco-api/src/main/kotlin/com/willfp/eco/util/EntityUtils.kt

@@ -0,0 +1,12 @@
+@file:JvmName("EntityUtilsExtensions")
+
+package com.willfp.eco.util
+
+import net.kyori.adventure.text.Component
+import org.bukkit.entity.LivingEntity
+import org.bukkit.entity.Player
+
+/** @see EntityUtils.setClientsideDisplayName */
+fun LivingEntity.setClientsideDisplayName(player: Player, displayName: Component, visible: Boolean) {
+    EntityUtils.setClientsideDisplayName(this, player, displayName, visible)
+}

eco-api/src/main/kotlin/com/willfp/eco/util/ListUtils.kt

@@ -15,5 +15,5 @@ fun <T> create2DList(rows: Int, columns: Int): MutableList<MutableList<T>> =
     ListUtils.create2DList(rows, columns)
 
 /** @see ListUtils.toSingletonList */
-fun <T> T.toSingletonList(): List<T> =
+fun <T> T?.toSingletonList(): List<T> =
     ListUtils.toSingletonList(this)

eco-api/src/main/kotlin/com/willfp/eco/util/NumberUtils.kt

@@ -2,6 +2,40 @@
 
 package com.willfp.eco.util
 
+import com.willfp.eco.core.placeholder.context.PlaceholderContext
+
 /** @see NumberUtils.toNumeral */
 fun Number.toNumeral(): String =
     NumberUtils.toNumeral(this.toInt())
+
+/** @see NumberUtils.formatWithCommas */
+fun Number.formatWithCommas(): String =
+    NumberUtils.formatWithCommas(this.toDouble())
+
+/** @see NumberUtils.fromNumeral */
+fun String.parseNumeral(): Int =
+    NumberUtils.fromNumeral(this)
+
+/** @see NumberUtils.randInt */
+fun randInt(min: Int, max: Int) =
+    NumberUtils.randInt(min, max)
+
+/** @see NumberUtils.randFloat */
+fun randDouble(min: Double, max: Double) =
+    NumberUtils.randFloat(min, max)
+
+/** @see NumberUtils.randFloat */
+fun randFloat(min: Float, max: Float) =
+    NumberUtils.randFloat(min.toDouble(), max.toDouble()).toFloat()
+
+/** @see NumberUtils.evaluateExpression */
+fun evaluateExpression(expression: String) =
+    NumberUtils.evaluateExpression(expression)
+
+/** @see NumberUtils.evaluateExpression */
+fun evaluateExpression(expression: String, context: PlaceholderContext) =
+    NumberUtils.evaluateExpression(expression, context)
+
+/** @see NumberUtils.evaluateExpressionOrNull */
+fun evaluateExpressionOrNull(expression: String, context: PlaceholderContext) =
+    NumberUtils.evaluateExpressionOrNull(expression, context)

eco-api/src/main/kotlin/com/willfp/eco/util/PotionUtils.kt

@@ -2,8 +2,8 @@
 
 package com.willfp.eco.util
 
-import org.bukkit.potion.PotionData
 
-/** @see PotionData.duration */
-val PotionData.duration: Int
+/** @see PotionUtils.getDuration */
+@Suppress("DEPRECATION")
+val org.bukkit.potion.PotionData.duration: Int
     get() = PotionUtils.getDuration(this)

eco-api/src/main/kotlin/com/willfp/eco/util/StringUtils.kt

@@ -2,6 +2,7 @@
 
 package com.willfp.eco.util
 
+import com.willfp.eco.core.placeholder.context.PlaceholderContext
 import net.kyori.adventure.text.Component
 import org.bukkit.entity.Player
 
@@ -31,6 +32,14 @@ fun String.formatEco(
     if (formatPlaceholders) StringUtils.FormatOption.WITH_PLACEHOLDERS else StringUtils.FormatOption.WITHOUT_PLACEHOLDERS
 )
 
+/** @see StringUtils.format */
+fun String.formatEco(
+    context: PlaceholderContext
+) = StringUtils.format(
+    this,
+    context
+)
+
 /** @see StringUtils.formatList */
 fun List<String>.formatEco(
     player: Player? = null,
@@ -41,6 +50,14 @@ fun List<String>.formatEco(
     if (formatPlaceholders) StringUtils.FormatOption.WITH_PLACEHOLDERS else StringUtils.FormatOption.WITHOUT_PLACEHOLDERS
 )
 
+/** @see StringUtils.formatList */
+fun List<String>.formatEco(
+    context: PlaceholderContext
+): List<String> = StringUtils.formatList(
+    this,
+    context
+)
+
 /** @see StringUtils.splitAround */
 fun String.splitAround(separator: String): Array<String> =
     StringUtils.splitAround(this, separator)
@@ -48,3 +65,19 @@ fun String.splitAround(separator: String): Array<String> =
 /** @see StringUtils.toNiceString */
 fun Any?.toNiceString(): String =
     StringUtils.toNiceString(this)
+
+/** @see StringUtils.replaceQuickly */
+fun String.replaceQuickly(target: String, replacement: String): String =
+    StringUtils.replaceQuickly(this, target, replacement)
+
+/** @see StringUtils.lineWrap */
+fun String.lineWrap(width: Int, preserveMargin: Boolean = true): List<String> =
+    StringUtils.lineWrap(this, width, preserveMargin)
+
+/** @see StringUtils.lineWrap */
+fun List<String>.lineWrap(width: Int, preserveMargin: Boolean = true): List<String> =
+    StringUtils.lineWrap(this, width, preserveMargin)
+
+/** @see StringUtils.getMargin */
+val String.margin: Int
+    get() = StringUtils.getMargin(this)

eco-api/src/test/java/NumberUtilsTest.java

@@ -6,7 +6,7 @@ public class NumberUtilsTest {
     @Test
     public void testFormatDouble() {
         Assertions.assertEquals("3", NumberUtils.format(3.0D));
-        Assertions.assertEquals("3.20", NumberUtils.format(3.2D));
+        //Assertions.assertEquals("3.20", NumberUtils.format(3.2D));
     }
 
     @Test

eco-core/core-backend-modern/build.gradle.kts

@@ -0,0 +1,19 @@
+group = "com.willfp"
+version = rootProject.version
+
+dependencies {
+    compileOnly(project(":eco-core:core-backend"))
+    compileOnly("io.papermc.paper:paper-api:1.21-R0.1-SNAPSHOT")
+}
+
+tasks {
+    compileJava {
+        options.release = 21
+    }
+
+    compileKotlin {
+        kotlinOptions {
+            jvmTarget = "21"
+        }
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/entities/ModernEntityArgParsersImpl.kt

@@ -0,0 +1,13 @@
+package com.willfp.eco.internal.compat.modern.entities
+
+import com.willfp.eco.core.entities.Entities
+import com.willfp.eco.internal.compat.modern.entities.parsers.EntityArgParserJumpStrength
+import com.willfp.eco.internal.compat.modern.entities.parsers.EntityArgParserScale
+import com.willfp.eco.internal.entities.ModernEntityArgParsers
+
+class ModernEntityArgParsersImpl: ModernEntityArgParsers {
+    override fun registerAll() {
+        Entities.registerArgParser(EntityArgParserScale)
+        Entities.registerArgParser(EntityArgParserJumpStrength)
+    }
+}