Reverted publication changes

This reverts commit feebbd8ec7.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,8 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Auxilor Community Discord
+    url: https://discord.gg/ZcwpSsE/
+    about: Join the Auxilor discord to get help from support staff and the general community!
+  - name: The most common issues people have
+    url: https://github.com/Auxilor/eco/issues/78
+    about: Check the list of known common issues to see if your issue has already been solved

.github/ISSUE_TEMPLATE/report-a-bug.md

@@ -0,0 +1,31 @@
+---
+name: Report a Bug
+about: Report an issue with the plugin
+title: ''
+labels: bug
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior: 
+1. Go to '...'
+2. Click on '....'
+3. Scroll down to '....'
+4. See error
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Screenshots**
+If applicable, add screenshots to help explain your problem.
+
+**Server Information (please complete the following information):**
+- Version: (output of `/ver` command)
+- Version of plugin and eco (`/ver eco`, `/ver <plugin>`)
+
+**Additional context**
+Add any other context about the problem here.

.github/ISSUE_TEMPLATE/request-a-feature.md

@@ -0,0 +1,20 @@
+---
+name: Request a Feature
+about: Suggest an idea for this plugin
+title: ''
+labels: enhancement
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+**Additional context**
+Add any other context or screenshots about the feature request here.

.github/workflows/test-publish.yml

@@ -0,0 +1,42 @@
+name: Publish API (Dev)
+
+on: [push]
+
+jobs:
+  publish-release:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout latest code
+        uses: actions/checkout@v2
+
+      - name: Set outputs
+        id: vars
+        run: echo "::set-output name=sha_short::$(git rev-parse --short HEAD)"
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v2
+        with:
+          distribution: 'temurin'
+          java-version: 17
+
+      - name: Setup build cache
+        uses: actions/cache@v2.1.6
+        with:
+          path: ~/.gradle/caches
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle.kts') }}
+          restore-keys: |
+            ${{ runner.os }}-gradle-
+
+
+      - name: Publish artifact
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+        # The GITHUB_REF tag comes in the format 'refs/tags/xxx'.
+        # So if we split on '/' and take the 3rd value, we can get the release name.
+        run: |
+          NEW_VERSION=$(echo "${GITHUB_REF}" | cut -d "/" -f3)
+          echo "New version: ${{ steps.vars.outputs.sha_short }}"
+          echo "Github username: ${GITHUB_ACTOR}"
+          ./gradlew -Pversion=${{ steps.vars.outputs.sha_short }} publish

build.gradle.kts

@@ -12,7 +12,7 @@ dependencies {
     implementation(project(":eco-core:core-backend"))
     implementation(project(":eco-core:core-nms:v1_16_R3"))
     implementation(project(path = ":eco-core:core-nms:v1_17_R1", configuration = "reobf"))
-    implementation(project(":eco-core:core-nms:v1_18_R1"))
+    implementation(project(path = ":eco-core:core-nms:v1_18_R1", configuration = "reobf"))
 }
 
 allprojects {
@@ -61,6 +61,15 @@ allprojects {
 
         // IridiumSkyblock
         maven("https://nexus.iridiumdevelopment.net/repository/maven-releases/")
+
+        // MythicMobs
+        maven("https://mvn.lumine.io/repository/maven-public/")
+
+        // Crunch
+        maven("https://redempt.dev")
+
+        // LibsDisguises
+        maven("https://repo.md-5.net/content/groups/public/")
     }
 
     dependencies {
@@ -74,6 +83,10 @@ allprojects {
         compileOnly("net.kyori:adventure-api:4.9.3")
         compileOnly("net.kyori:adventure-text-serializer-gson:4.9.3")
         compileOnly("net.kyori:adventure-text-serializer-legacy:4.9.3")
+
+        // Other
+        compileOnly("com.google.guava:guava:31.0.1-jre")
+        compileOnly("com.github.ben-manes.caffeine:caffeine:3.0.5")
     }
 
     tasks.withType<JavaCompile> {

eco-api/build.gradle

@@ -1,11 +1,19 @@
-plugins {
-    id 'com.github.johnrengelman.shadow'
+buildscript {
+    repositories {
+        mavenCentral()
+    }
+
+    dependencies {
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.6.0"
+    }
 }
 
-group 'com.willfp'
-version rootProject.version
+apply plugin: 'kotlin'
 
 dependencies {
+    // Kotlin
+    compileOnly 'org.jetbrains.kotlin:kotlin-stdlib:1.6.0'
+
     // Adventure
     compileOnly 'net.kyori:adventure-platform-bukkit:4.0.0'
     compileOnly 'net.kyori:adventure-text-minimessage:4.1.0-SNAPSHOT'
@@ -17,10 +25,20 @@ dependencies {
     compileOnly 'com.google.code.gson:gson:2.8.8'
 }
 
+compileKotlin {
+    kotlinOptions {
+        jvmTarget = "17"
+    }
+    targetCompatibility = JavaVersion.VERSION_17
+    sourceCompatibility = JavaVersion.VERSION_17
+}
+
 java {
     withJavadocJar()
 }
 
+group 'com.willfp'
+version rootProject.version
 
 build.dependsOn publishToMavenLocal
 

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

@@ -4,6 +4,12 @@ import org.apache.commons.lang.Validate;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
 /**
  * Holds the instance of the eco handler for bridging between the frontend
  * and backend.
@@ -52,6 +58,24 @@ public final class Eco {
         return handler;
     }
 
+    /**
+     * Eco Handler components are internals, so if a class is marked as a handler component,
+     * then it should be treated the same as if it was marked with {@link ApiStatus.Internal}.
+     * <p>
+     * If a class is marked with {@link HandlerComponent}, <strong>Do not reference it in
+     * your code!</strong> It can and will contain breaking changes between minor versions and
+     * even patches, and you will create compatibility issues by using them.
+     * <p>
+     * Handler components should also be marked with {@link ApiStatus.Internal} in order to
+     * cause compiler / IDE warnings.
+     */
+    @Documented
+    @Retention(RetentionPolicy.CLASS)
+    @Target({ElementType.TYPE})
+    public @interface HandlerComponent {
+
+    }
+
     private Eco() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }

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

@@ -327,11 +327,9 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike {
                 DefaultArtifactVersion mostRecentVersion = new DefaultArtifactVersion(version);
                 if (!(currentVersion.compareTo(mostRecentVersion) > 0 || currentVersion.equals(mostRecentVersion))) {
                     this.outdated = true;
-                    this.getScheduler().runTimer(() -> {
-                        this.getLogger().info("&c " + this.getName() + " is out of date! (Version " + this.getDescription().getVersion() + ")");
-                        this.getLogger().info("&cThe newest version is &f" + version);
-                        this.getLogger().info("&cDownload the new version!");
-                    }, 0, 864000);
+                    this.getLogger().warning("&c" + this.getName() + " is out of date! (Version " + this.getDescription().getVersion() + ")");
+                    this.getLogger().warning("&cThe newest version is &f" + version);
+                    this.getLogger().warning("&cDownload the new version!");
                 }
             });
         }

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

@@ -2,7 +2,7 @@ package com.willfp.eco.core;
 
 import com.willfp.eco.core.config.updating.ConfigHandler;
 import com.willfp.eco.core.config.wrapper.ConfigFactory;
-import com.willfp.eco.core.data.PlayerProfileHandler;
+import com.willfp.eco.core.data.ProfileHandler;
 import com.willfp.eco.core.data.keys.KeyRegistry;
 import com.willfp.eco.core.drops.DropQueueFactory;
 import com.willfp.eco.core.events.EventManager;
@@ -18,6 +18,9 @@ import com.willfp.eco.core.proxy.ProxyFactory;
 import com.willfp.eco.core.requirement.RequirementFactory;
 import com.willfp.eco.core.scheduling.Scheduler;
 import net.kyori.adventure.platform.bukkit.BukkitAudiences;
+import org.bukkit.Location;
+import org.bukkit.NamespacedKey;
+import org.bukkit.entity.Entity;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
@@ -231,5 +234,29 @@ public interface Handler {
      * @return The handler.
      */
     @NotNull
-    PlayerProfileHandler getPlayerProfileHandler();
+    ProfileHandler getProfileHandler();
+
+    /**
+     * Create dummy entity - never spawned, exists purely in code.
+     *
+     * @param location The location.
+     * @return The entity.
+     */
+    @NotNull
+    Entity createDummyEntity(@NotNull Location location);
+
+    /**
+     * Create a {@link NamespacedKey} quickly
+     * <p>
+     * Bypasses the constructor, allowing for the creation of invalid keys,
+     * therefore this is considered unsafe and should only be called after
+     * the key has been confirmed to be valid.
+     *
+     * @param namespace The namespace.
+     * @param key       The key.
+     * @return The key.
+     */
+    @NotNull
+    NamespacedKey createNamespacedKey(@NotNull String namespace,
+                                      @NotNull String key);
 }

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

@@ -1,11 +1,16 @@
 package com.willfp.eco.core.config.interfaces;
 
 import com.willfp.eco.core.config.ConfigType;
+import com.willfp.eco.core.config.TransientConfig;
+import com.willfp.eco.util.NumberUtils;
 import com.willfp.eco.util.StringUtils;
+import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 /**
  * All configs implement this interface.
@@ -67,10 +72,12 @@ public interface Config extends Cloneable {
      * Get subsection from config.
      *
      * @param path The key to check.
-     * @return The subsection. Throws NPE if not found.
+     * @return The subsection. Returns an empty section if not found.
      */
     @NotNull
-    Config getSubsection(@NotNull String path);
+    default Config getSubsection(@NotNull String path) {
+        return Objects.requireNonNullElse(getSubsectionOrNull(path), new TransientConfig());
+    }
 
     /**
      * Get subsection from config.
@@ -87,7 +94,44 @@ public interface Config extends Cloneable {
      * @param path The key to fetch the value from.
      * @return The found value, or 0 if not found.
      */
-    int getInt(@NotNull String path);
+    default int getInt(@NotNull String path) {
+        return Objects.requireNonNullElse(getIntOrNull(path), 0);
+    }
+
+    /**
+     * Get an integer from config with a specified default (not found) value.
+     *
+     * @param path The key to fetch the value from.
+     * @param def  The value to default to if not found.
+     * @return The found value, or the default.
+     */
+    default int getInt(@NotNull String path,
+                       int def) {
+        return Objects.requireNonNullElse(getIntOrNull(path), def);
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path The key to fetch the value from.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default int getIntFromExpression(@NotNull String path) {
+        return getIntFromExpression(path, null);
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path   The key to fetch the value from.
+     * @param player The player to evaluate placeholders with respect to.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default int getIntFromExpression(@NotNull String path,
+                                     @Nullable Player player) {
+        return Double.valueOf(getDoubleFromExpression(path, player)).intValue();
+    }
+
 
     /**
      * Get an integer from config.
@@ -98,16 +142,6 @@ public interface Config extends Cloneable {
     @Nullable
     Integer getIntOrNull(@NotNull String path);
 
-    /**
-     * Get an integer from config with a specified default (not found) value.
-     *
-     * @param path The key to fetch the value from.
-     * @param def  The value to default to if not found.
-     * @return The found value, or the default.
-     */
-    int getInt(@NotNull String path,
-               int def);
-
     /**
      * Get a list of integers from config.
      *
@@ -115,7 +149,9 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<Integer> getInts(@NotNull String path);
+    default List<Integer> getInts(@NotNull String path) {
+        return Objects.requireNonNullElse(getIntsOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of integers from config.
@@ -132,7 +168,9 @@ public interface Config extends Cloneable {
      * @param path The key to fetch the value from.
      * @return The found value, or false if not found.
      */
-    boolean getBool(@NotNull String path);
+    default boolean getBool(@NotNull String path) {
+        return Objects.requireNonNullElse(getBoolOrNull(path), false);
+    }
 
     /**
      * Get a boolean from config.
@@ -150,7 +188,9 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<Boolean> getBools(@NotNull String path);
+    default List<Boolean> getBools(@NotNull String path) {
+        return Objects.requireNonNullElse(getBoolsOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of booleans from config.
@@ -169,7 +209,7 @@ public interface Config extends Cloneable {
      */
     @NotNull
     default String getFormattedString(@NotNull String path) {
-        return getString(path, true);
+        return getString(path, true, StringUtils.FormatOption.WITH_PLACEHOLDERS);
     }
 
     /**
@@ -188,25 +228,25 @@ public interface Config extends Cloneable {
     /**
      * Get a string from config.
      * <p>
-     * Formatted by default.
+     * Not formatted.
      *
      * @param path The key to fetch the value from.
      * @return The found value, or an empty string if not found.
      */
     @NotNull
     default String getString(@NotNull String path) {
-        return getString(path, true);
+        return getString(path, false);
     }
 
     /**
      * Get a string from config.
-     * <p>
-     * This will be deprecated when {@link Config#getString(String)} no longer formats by default.
      *
      * @param path   The key to fetch the value from.
      * @param format If the string should be formatted.
      * @return The found value, or an empty string if not found.
+     * @deprecated Since 6.18.0, {@link Config#getString(String)} is not formatted by default.
      */
+    @Deprecated(since = "6.18.0")
     default String getString(@NotNull String path,
                              boolean format) {
         return this.getString(path, format, StringUtils.FormatOption.WITH_PLACEHOLDERS);
@@ -236,9 +276,11 @@ public interface Config extends Cloneable {
      * @return The found value, or an empty string if not found.
      */
     @NotNull
-    String getString(@NotNull String path,
-                     boolean format,
-                     @NotNull StringUtils.FormatOption option);
+    default String getString(@NotNull String path,
+                             boolean format,
+                             @NotNull StringUtils.FormatOption option) {
+        return Objects.requireNonNullElse(getStringOrNull(path, format, option), "");
+    }
 
     /**
      * Get a formatted string from config.
@@ -248,7 +290,7 @@ public interface Config extends Cloneable {
      */
     @Nullable
     default String getFormattedStringOrNull(@NotNull String path) {
-        return getStringOrNull(path, true);
+        return getStringOrNull(path, true, StringUtils.FormatOption.WITH_PLACEHOLDERS);
     }
 
     /**
@@ -274,19 +316,19 @@ public interface Config extends Cloneable {
      */
     @Nullable
     default String getStringOrNull(@NotNull String path) {
-        return getStringOrNull(path, true);
+        return getStringOrNull(path, false, StringUtils.FormatOption.WITH_PLACEHOLDERS);
     }
 
     /**
      * Get a string from config.
-     * <p>
-     * This will be deprecated when {@link Config#getStringOrNull(String)} no longer formats by default.
      *
      * @param path   The key to fetch the value from.
      * @param format If the string should be formatted.
      * @return The found value, or null if not found.
+     * @deprecated Since 6.18.0, {@link Config#getString(String)} is not formatted by default.
      */
     @Nullable
+    @Deprecated(since = "6.18.0")
     default String getStringOrNull(@NotNull String path,
                                    boolean format) {
         return this.getStringOrNull(path, format, StringUtils.FormatOption.WITH_PLACEHOLDERS);
@@ -351,28 +393,26 @@ public interface Config extends Cloneable {
     /**
      * Get a list of strings from config.
      * <p>
-     * Formatted by default.
-     * <p>
-     * This will be changed in newer versions to <b>not</b> format by default.
+     * Not formatted.
      *
      * @param path The key to fetch the value from.
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
     default List<String> getStrings(@NotNull String path) {
-        return getStrings(path, true);
+        return getStrings(path, false, StringUtils.FormatOption.WITH_PLACEHOLDERS);
     }
 
     /**
      * Get a list of strings from config.
-     * <p>
-     * This will be deprecated when {@link Config#getStrings(String)} no longer formats by default.
      *
      * @param path   The key to fetch the value from.
      * @param format If the strings should be formatted.
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
+     * @deprecated Since 6.18.0, {@link Config#getString(String)} is not formatted by default.
      */
     @NotNull
+    @Deprecated(since = "6.18.0")
     default List<String> getStrings(@NotNull String path,
                                     boolean format) {
         return this.getStrings(path, format, StringUtils.FormatOption.WITH_PLACEHOLDERS);
@@ -390,7 +430,7 @@ public interface Config extends Cloneable {
     @Deprecated
     default List<String> getStrings(@NotNull String path,
                                     @NotNull StringUtils.FormatOption option) {
-        return getStrings(path, true, option);
+        return getStrings(path, false, option);
     }
 
     /**
@@ -402,14 +442,16 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<String> getStrings(@NotNull String path,
-                            boolean format,
-                            @NotNull StringUtils.FormatOption option);
+    default List<String> getStrings(@NotNull String path,
+                                    boolean format,
+                                    @NotNull StringUtils.FormatOption option) {
+        return Objects.requireNonNullElse(getStringsOrNull(path, format, option), new ArrayList<>());
+    }
 
     /**
      * Get a list of strings from config.
      * <p>
-     * Formatted by default.
+     * Formatted.
      *
      * @param path The key to fetch the value from.
      * @return The found value, or null if not found.
@@ -422,7 +464,7 @@ public interface Config extends Cloneable {
     /**
      * Get a list of strings from config.
      * <p>
-     * Formatted by default.
+     * Formatted.
      *
      * @param path   The key to fetch the value from.
      * @param option The format option.
@@ -437,7 +479,7 @@ public interface Config extends Cloneable {
     /**
      * Get a list of strings from config.
      * <p>
-     * Formatted by default.
+     * Not formatted.
      * <p>
      * This will be changed in newer versions to <b>not</b> format by default.
      *
@@ -446,7 +488,7 @@ public interface Config extends Cloneable {
      */
     @Nullable
     default List<String> getStringsOrNull(@NotNull String path) {
-        return getStringsOrNull(path, true);
+        return getStringsOrNull(path, false, StringUtils.FormatOption.WITH_PLACEHOLDERS);
     }
 
     /**
@@ -455,8 +497,10 @@ public interface Config extends Cloneable {
      * @param path   The key to fetch the value from.
      * @param format If the strings should be formatted.
      * @return The found value, or null if not found.
+     * @deprecated Since 6.18.0, {@link Config#getString(String)} is not formatted by default.
      */
     @Nullable
+    @Deprecated(since = "6.18.0")
     default List<String> getStringsOrNull(@NotNull String path,
                                           boolean format) {
         return getStringsOrNull(path, format, StringUtils.FormatOption.WITH_PLACEHOLDERS);
@@ -474,7 +518,7 @@ public interface Config extends Cloneable {
     @Deprecated
     default List<String> getStringsOrNull(@NotNull String path,
                                           @NotNull StringUtils.FormatOption option) {
-        return getStringsOrNull(path, true, option);
+        return getStringsOrNull(path, false, option);
     }
 
     /**
@@ -496,7 +540,31 @@ public interface Config extends Cloneable {
      * @param path The key to fetch the value from.
      * @return The found value, or 0 if not found.
      */
-    double getDouble(@NotNull String path);
+    default double getDouble(@NotNull String path) {
+        return Objects.requireNonNullElse(getDoubleOrNull(path), 0.0);
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path The key to fetch the value from.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default double getDoubleFromExpression(@NotNull String path) {
+        return getDoubleFromExpression(path, null);
+    }
+
+    /**
+     * Get a decimal value via a mathematical expression.
+     *
+     * @param path   The key to fetch the value from.
+     * @param player The player to evaluate placeholders with respect to.
+     * @return The computed value, or 0 if not found or invalid.
+     */
+    default double getDoubleFromExpression(@NotNull String path,
+                                           @Nullable Player player) {
+        return NumberUtils.evaluateExpression(this.getString(path), player);
+    }
 
     /**
      * Get a decimal from config.
@@ -514,7 +582,9 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<Double> getDoubles(@NotNull String path);
+    default List<Double> getDoubles(@NotNull String path) {
+        return Objects.requireNonNullElse(getDoublesOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of decimals from config.
@@ -532,7 +602,9 @@ public interface Config extends Cloneable {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<? extends Config> getSubsections(@NotNull String path);
+    default List<? extends Config> getSubsections(@NotNull String path) {
+        return Objects.requireNonNullElse(getSubsectionsOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of subsections from config.

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

@@ -3,7 +3,9 @@ package com.willfp.eco.core.config.interfaces;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 /**
  * JSON config.
@@ -22,7 +24,9 @@ public interface JSONConfig extends Config {
      * @return The found value, or a blank {@link java.util.ArrayList} if not found.
      */
     @NotNull
-    List<JSONConfig> getSubsections(@NotNull String path);
+    default List<JSONConfig> getSubsections(@NotNull String path) {
+        return Objects.requireNonNullElse(getSubsectionsOrNull(path), new ArrayList<>());
+    }
 
     /**
      * Get a list of subsections from config.

eco-api/src/main/java/com/willfp/eco/core/config/wrapper/ConfigFactory.java

@@ -1,5 +1,6 @@
 package com.willfp.eco.core.config.wrapper;
 
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.PluginLike;
 import com.willfp.eco.core.config.ConfigType;
 import com.willfp.eco.core.config.interfaces.Config;
@@ -14,6 +15,7 @@ import java.util.Map;
  * Internal component to create backend config implementations.
  */
 @ApiStatus.Internal
+@Eco.HandlerComponent
 public interface ConfigFactory {
     /**
      * Updatable config.

eco-api/src/main/java/com/willfp/eco/core/config/wrapper/ConfigWrapper.java

@@ -70,70 +70,31 @@ public abstract class ConfigWrapper<T extends Config> implements Config {
         handle.set(path, object);
     }
 
-    @Override
-    public @NotNull Config getSubsection(@NotNull final String path) {
-        return handle.getSubsection(path);
-    }
-
     @Override
     public @Nullable Config getSubsectionOrNull(@NotNull final String path) {
         return handle.getSubsectionOrNull(path);
     }
 
-    @Override
-    public int getInt(@NotNull final String path) {
-        return handle.getInt(path);
-    }
-
     @Override
     public @Nullable Integer getIntOrNull(@NotNull final String path) {
         return handle.getIntOrNull(path);
     }
 
-    @Override
-    public int getInt(@NotNull final String path,
-                      final int def) {
-        return handle.getInt(path, def);
-    }
-
-    @Override
-    public @NotNull List<Integer> getInts(@NotNull final String path) {
-        return handle.getInts(path);
-    }
-
     @Override
     public @Nullable List<Integer> getIntsOrNull(@NotNull final String path) {
         return handle.getIntsOrNull(path);
     }
 
-    @Override
-    public boolean getBool(@NotNull final String path) {
-        return handle.getBool(path);
-    }
-
     @Override
     public @Nullable Boolean getBoolOrNull(@NotNull final String path) {
         return handle.getBoolOrNull(path);
     }
 
-    @Override
-    public @NotNull List<Boolean> getBools(@NotNull final String path) {
-        return handle.getBools(path);
-    }
-
     @Override
     public @Nullable List<Boolean> getBoolsOrNull(@NotNull final String path) {
         return handle.getBoolsOrNull(path);
     }
 
-
-    @Override
-    public @NotNull String getString(@NotNull final String path,
-                                     final boolean format,
-                                     @NotNull final StringUtils.FormatOption option) {
-        return handle.getString(path, format, option);
-    }
-
     @Override
     public @Nullable String getStringOrNull(@NotNull final String path,
                                             final boolean format,
@@ -141,13 +102,6 @@ public abstract class ConfigWrapper<T extends Config> implements Config {
         return handle.getStringOrNull(path, format, option);
     }
 
-    @Override
-    public @NotNull List<String> getStrings(@NotNull final String path,
-                                            final boolean format,
-                                            @NotNull final StringUtils.FormatOption option) {
-        return handle.getStrings(path, format, option);
-    }
-
     @Override
     public @Nullable List<String> getStringsOrNull(@NotNull final String path,
                                                    final boolean format,
@@ -155,31 +109,16 @@ public abstract class ConfigWrapper<T extends Config> implements Config {
         return handle.getStringsOrNull(path, format, option);
     }
 
-    @Override
-    public double getDouble(@NotNull final String path) {
-        return handle.getDouble(path);
-    }
-
     @Override
     public @Nullable Double getDoubleOrNull(@NotNull final String path) {
         return handle.getDoubleOrNull(path);
     }
 
-    @Override
-    public @NotNull List<Double> getDoubles(@NotNull final String path) {
-        return handle.getDoubles(path);
-    }
-
     @Override
     public @Nullable List<Double> getDoublesOrNull(@NotNull final String path) {
         return handle.getDoublesOrNull(path);
     }
 
-    @Override
-    public @NotNull List<? extends Config> getSubsections(@NotNull final String path) {
-        return handle.getSubsections(path);
-    }
-
     @Override
     public @Nullable List<? extends Config> getSubsectionsOrNull(@NotNull final String path) {
         return handle.getSubsectionsOrNull(path);

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

@@ -1,7 +1,6 @@
 package com.willfp.eco.core.data;
 
 import com.willfp.eco.core.Eco;
-import com.willfp.eco.core.data.keys.PersistentDataKey;
 import org.bukkit.OfflinePlayer;
 import org.jetbrains.annotations.NotNull;
 
@@ -12,26 +11,7 @@ import java.util.UUID;
  * <p>
  * Profiles save automatically, so there is no need to save after changes.
  */
-public interface PlayerProfile {
-    /**
-     * Write a key to a player's persistent data.
-     *
-     * @param key   The key.
-     * @param value The value.
-     * @param <T>   The type of the key.
-     */
-    <T> void write(@NotNull PersistentDataKey<T> key,
-                   @NotNull T value);
-
-    /**
-     * Read a key from a player's persistent data.
-     *
-     * @param key The key.
-     * @param <T> The type of the key.
-     * @return The value, or the default value if not found.
-     */
-    <T> @NotNull T read(@NotNull PersistentDataKey<T> key);
-
+public interface PlayerProfile extends Profile {
     /**
      * Load a player profile.
      *
@@ -51,6 +31,6 @@ public interface PlayerProfile {
      */
     @NotNull
     static PlayerProfile load(@NotNull final UUID uuid) {
-        return Eco.getHandler().getPlayerProfileHandler().load(uuid);
+        return Eco.getHandler().getProfileHandler().load(uuid);
     }
 }

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

@@ -0,0 +1,30 @@
+package com.willfp.eco.core.data;
+
+import com.willfp.eco.core.data.keys.PersistentDataKey;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Persistent data storage interface.
+ * <p>
+ * Profiles save automatically, so there is no need to save after changes.
+ */
+public interface Profile {
+    /**
+     * Write a key to persistent data.
+     *
+     * @param key   The key.
+     * @param value The value.
+     * @param <T>   The type of the key.
+     */
+    <T> void write(@NotNull PersistentDataKey<T> key,
+                   @NotNull T value);
+
+    /**
+     * Read a key from persistent data.
+     *
+     * @param key The key.
+     * @param <T> The type of the key.
+     * @return The value, or the default value if not found.
+     */
+    <T> @NotNull T read(@NotNull PersistentDataKey<T> key);
+}

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

@@ -1,15 +1,19 @@
 package com.willfp.eco.core.data;
 
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.data.keys.PersistentDataKey;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Set;
 import java.util.UUID;
 
 /**
- * API to handle player profiles.
+ * API to handle profiles.
  */
-public interface PlayerProfileHandler {
+@ApiStatus.Internal
+@Eco.HandlerComponent
+public interface ProfileHandler {
     /**
      * Load a player profile.
      *
@@ -18,6 +22,13 @@ public interface PlayerProfileHandler {
      */
     PlayerProfile load(@NotNull UUID uuid);
 
+    /**
+     * Load the server profile.
+     *
+     * @return The profile.
+     */
+    ServerProfile loadServerProfile();
+
     /**
      * Unload a player profile from memory.
      * <p>
@@ -37,7 +48,7 @@ public interface PlayerProfileHandler {
      */
     @Deprecated
     default void savePlayer(@NotNull UUID uuid) {
-        this.saveKeysForPlayer(uuid, PersistentDataKey.values());
+        this.saveKeysFor(uuid, PersistentDataKey.values());
     }
 
     /**
@@ -48,8 +59,8 @@ public interface PlayerProfileHandler {
      * @param uuid The uuid.
      * @param keys The keys.
      */
-    void saveKeysForPlayer(@NotNull UUID uuid,
-                           @NotNull Set<PersistentDataKey<?>> keys);
+    void saveKeysFor(@NotNull UUID uuid,
+                     @NotNull Set<PersistentDataKey<?>> keys);
 
     /**
      * Save all player data.

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

@@ -0,0 +1,21 @@
+package com.willfp.eco.core.data;
+
+import com.willfp.eco.core.Eco;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Persistent data storage interface for servers.
+ * <p>
+ * Profiles save automatically, so there is no need to save after changes.
+ */
+public interface ServerProfile extends Profile {
+    /**
+     * Load the server profile.
+     *
+     * @return The profile.
+     */
+    @NotNull
+    static ServerProfile load() {
+        return Eco.getHandler().getProfileHandler().loadServerProfile();
+    }
+}

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

@@ -25,7 +25,7 @@ public class PersistentDataKey<T> {
     /**
      * The persistent data key type.
      */
-    private final PersistentDataKeyType type;
+    private final PersistentDataKeyType<T> type;
 
     /**
      * Create a new Persistent Data Key.
@@ -35,7 +35,7 @@ public class PersistentDataKey<T> {
      * @param defaultValue The default value.
      */
     public PersistentDataKey(@NotNull final NamespacedKey key,
-                             @NotNull final PersistentDataKeyType type,
+                             @NotNull final PersistentDataKeyType<T> type,
                              @NotNull final T defaultValue) {
         this.key = key;
         this.defaultValue = defaultValue;
@@ -53,15 +53,6 @@ public class PersistentDataKey<T> {
                 + '}';
     }
 
-    /**
-     * Get all persistent data keys.
-     *
-     * @return The keys.
-     */
-    public static Set<PersistentDataKey<?>> values() {
-        return Eco.getHandler().getKeyRegistry().getRegisteredKeys();
-    }
-
     /**
      * Get the key.
      *
@@ -85,7 +76,16 @@ public class PersistentDataKey<T> {
      *
      * @return The key type.
      */
-    public PersistentDataKeyType getType() {
+    public PersistentDataKeyType<T> getType() {
         return this.type;
     }
+
+    /**
+     * Get all persistent data keys.
+     *
+     * @return The keys.
+     */
+    public static Set<PersistentDataKey<?>> values() {
+        return Eco.getHandler().getKeyRegistry().getRegisteredKeys();
+    }
 }

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

@@ -1,26 +1,108 @@
 package com.willfp.eco.core.data.keys;
 
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * All storable data key types.
+ *
+ * @param <T> The type.
  */
-public enum PersistentDataKeyType {
+public final class PersistentDataKeyType<T> {
+    /**
+     * The registered key types.
+     */
+    private static final List<PersistentDataKeyType<?>> VALUES = new ArrayList<>();
+
     /**
      * String.
      */
-    STRING,
+    public static final PersistentDataKeyType<String> STRING = new PersistentDataKeyType<>(String.class, "STRING");
 
     /**
      * Boolean.
      */
-    BOOLEAN,
+    public static final PersistentDataKeyType<Boolean> BOOLEAN = new PersistentDataKeyType<>(Boolean.class, "BOOLEAN");
 
     /**
-     * Integer.
+     * Int.
      */
-    INT,
+    public static final PersistentDataKeyType<Integer> INT = new PersistentDataKeyType<>(Integer.class, "INT");
 
     /**
      * Double.
      */
-    DOUBLE
+    public static final PersistentDataKeyType<Double> DOUBLE = new PersistentDataKeyType<>(Double.class, "DOUBLE");
+
+    /**
+     * The class of the type.
+     */
+    private final Class<T> typeClass;
+
+    /**
+     * The name of the key type.
+     */
+    private final String name;
+
+    /**
+     * Get the class of the type.
+     *
+     * @return The class.
+     */
+    public Class<T> getTypeClass() {
+        return typeClass;
+    }
+
+    /**
+     * Get the name of the key type.
+     *
+     * @return The name.
+     */
+    public String name() {
+        return name;
+    }
+
+    /**
+     * Create new PersistentDataKeyType.
+     *
+     * @param typeClass The type class.
+     * @param name      The name.
+     */
+    private PersistentDataKeyType(@NotNull final Class<T> typeClass,
+                                  @NotNull final String name) {
+        VALUES.add(this);
+
+        this.typeClass = typeClass;
+        this.name = name;
+    }
+
+    /**
+     * Get all registered {@link PersistentDataKeyType}s.
+     *
+     * @return The registered types.
+     */
+    @NotNull
+    public static PersistentDataKeyType<?>[] values() {
+        return VALUES.toArray(new PersistentDataKeyType[0]);
+    }
+
+    /**
+     * Get a key type from a name.
+     *
+     * @param name The name.
+     * @return The type, or null if not found.
+     */
+    @Nullable
+    public static PersistentDataKeyType<?> valueOf(@NotNull final String name) {
+        for (PersistentDataKeyType<?> type : VALUES) {
+            if (type.name.equalsIgnoreCase(name)) {
+                return type;
+            }
+        }
+
+        return null;
+    }
 }

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

@@ -1,13 +1,17 @@
 package com.willfp.eco.core.display;
 
+import com.willfp.eco.core.Eco;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 /**
  * Interface for display implementations.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface DisplayHandler {
     /**
      * Register display module.

eco-api/src/main/java/com/willfp/eco/core/drops/DropQueueFactory.java

@@ -1,11 +1,15 @@
 package com.willfp.eco.core.drops;
 
+import com.willfp.eco.core.Eco;
 import org.bukkit.entity.Player;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Internal component to create backend DropQueue implementations.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface DropQueueFactory {
     /**
      * Create a DropQueue.

eco-api/src/main/java/com/willfp/eco/core/drops/InternalDropQueue.java

@@ -1,7 +1,9 @@
 package com.willfp.eco.core.drops;
 
+import com.willfp.eco.core.Eco;
 import org.bukkit.Location;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Collection;
@@ -9,6 +11,8 @@ import java.util.Collection;
 /**
  * Internal interface for backend DropQueue implementations.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface InternalDropQueue {
     /**
      * Add item to queue.

eco-api/src/main/java/com/willfp/eco/core/entities/CustomEntity.java

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

eco-api/src/main/java/com/willfp/eco/core/entities/Entities.java

@@ -0,0 +1,239 @@
+package com.willfp.eco.core.entities;
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult;
+import com.willfp.eco.core.entities.args.EntityArgParser;
+import com.willfp.eco.core.entities.impl.EmptyTestableEntity;
+import com.willfp.eco.core.entities.impl.ModifiedTestableEntity;
+import com.willfp.eco.core.entities.impl.SimpleTestableEntity;
+import com.willfp.eco.util.NamespacedKeyUtils;
+import com.willfp.eco.util.StringUtils;
+import org.bukkit.Location;
+import org.bukkit.NamespacedKey;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.EntityType;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Function;
+
+/**
+ * Class to manage all custom and vanilla entities.
+ */
+public final class Entities {
+    /**
+     * All entities.
+     */
+    private static final Map<NamespacedKey, TestableEntity> REGISTRY = new ConcurrentHashMap<>();
+
+    /**
+     * All entity parsers.
+     */
+    private static final List<EntityArgParser> ARG_PARSERS = new ArrayList<>();
+
+    /**
+     * Register a new custom item.
+     *
+     * @param key  The key of the item.
+     * @param item The item.
+     */
+    public static void registerCustomEntity(@NotNull final NamespacedKey key,
+                                            @NotNull final TestableEntity item) {
+        REGISTRY.put(key, item);
+    }
+
+    /**
+     * Register a new arg parser.
+     *
+     * @param parser The parser.
+     */
+    public static void registerArgParser(@NotNull final EntityArgParser parser) {
+        ARG_PARSERS.add(parser);
+    }
+
+    /**
+     * Remove an entity.
+     *
+     * @param key The key of the entity.
+     */
+    public static void removeCustomEntity(@NotNull final NamespacedKey key) {
+        REGISTRY.remove(key);
+    }
+
+    /**
+     * This is the backbone of the entire eco entity system.
+     * <p>
+     * You can look up a TestableEntity for any type or custom entity,
+     * and it will return it with any modifiers passed as parameters.
+     * <p>
+     * If you want to get an Entity instance from this, then just call
+     * {@link TestableEntity#spawn(Location)}.
+     * <p>
+     * The advantages of the testable entity system are that there is the inbuilt
+     * {@link TestableEntity#matches(Entity)} - this allows to check if any entity
+     * is that testable entity; which may sound negligible, but actually it allows for
+     * much more power and flexibility. For example, you can have an entity with an
+     * extra metadata tag, extra lore lines, different display name - and it
+     * will still work as long as the test passes.
+     *
+     * @param key The lookup string.
+     * @return The testable entity, or an empty testable entity if not found.
+     */
+    @NotNull
+    public static TestableEntity lookup(@NotNull final String key) {
+        if (key.contains("?")) {
+            String[] options = key.split("\\?");
+            for (String option : options) {
+                TestableEntity lookup = lookup(option);
+                if (!(lookup instanceof EmptyTestableEntity)) {
+                    return lookup;
+                }
+            }
+
+            return new EmptyTestableEntity();
+        }
+
+        String[] args = StringUtils.parseTokens(key);
+
+        if (args.length == 0) {
+            return new EmptyTestableEntity();
+        }
+
+        TestableEntity entity;
+
+        String[] split = args[0].toLowerCase().split(":");
+
+        if (split.length == 1) {
+            EntityType type;
+            try {
+                type = EntityType.valueOf(args[0].toUpperCase());
+            } catch (IllegalArgumentException e) {
+                return new EmptyTestableEntity();
+            }
+            entity = new SimpleTestableEntity(type);
+        } else {
+            String namespace = split[0];
+            String keyID = split[1];
+            NamespacedKey namespacedKey = NamespacedKeyUtils.create(namespace, keyID);
+
+            TestableEntity part = REGISTRY.get(namespacedKey);
+
+            if (part == null) {
+                return new EmptyTestableEntity();
+            }
+
+            entity = part;
+        }
+
+
+        String[] modifierArgs = Arrays.copyOfRange(args, 1, args.length);
+
+        List<EntityArgParseResult> parseResults = new ArrayList<>();
+
+        for (EntityArgParser argParser : ARG_PARSERS) {
+            EntityArgParseResult result = argParser.parseArguments(modifierArgs);
+            if (result != null) {
+                parseResults.add(result);
+            }
+        }
+
+        Function<Location, Entity> spawner = entity::spawn;
+
+        if (!parseResults.isEmpty()) {
+            entity = new ModifiedTestableEntity(
+                    entity,
+                    test -> {
+                        for (EntityArgParseResult parseResult : parseResults) {
+                            if (!parseResult.test().test(test)) {
+                                return false;
+                            }
+                        }
+
+                        return true;
+                    },
+                    location -> {
+                        Entity spawned = spawner.apply(location);
+
+                        for (EntityArgParseResult parseResult : parseResults) {
+                            parseResult.modifier().accept(spawned);
+                        }
+
+                        return spawned;
+                    }
+            );
+        }
+
+        return entity;
+    }
+
+
+    /**
+     * Get a Testable Entity from an ItemStack.
+     * <p>
+     * Will search for registered entity first. If there are no matches in the registry,
+     * then it will return a {@link com.willfp.eco.core.entities.impl.SimpleTestableEntity} matching the entity type.
+     * <p>
+     * If the entity is not custom and has unknown type, this will return null.
+     *
+     * @param entity The Entity.
+     * @return The found Testable Entity.
+     */
+    @Nullable
+    public static TestableEntity getEntity(@Nullable final Entity entity) {
+        if (entity == null) {
+            return null;
+        }
+
+        TestableEntity customEntity = getEntity(entity);
+
+        if (customEntity != null) {
+            return customEntity;
+        }
+
+        for (TestableEntity known : REGISTRY.values()) {
+            if (known.matches(entity)) {
+                return known;
+            }
+        }
+
+        if (entity.getType() == EntityType.UNKNOWN) {
+            return null;
+        }
+
+        return new SimpleTestableEntity(entity.getType());
+    }
+
+    /**
+     * Get if entity is a custom entity.
+     *
+     * @param entity The entity to check.
+     * @return If is custom.
+     */
+    public static boolean isCustomEntity(@NotNull final Entity entity) {
+        for (TestableEntity testable : REGISTRY.values()) {
+            if (testable.matches(entity)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Get all registered custom items.
+     *
+     * @return A set of all items.
+     */
+    public static Set<TestableEntity> getCustomEntities() {
+        return new HashSet<>(REGISTRY.values());
+    }
+
+    private Entities() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/TestableEntity.java

@@ -0,0 +1,27 @@
+package com.willfp.eco.core.entities;
+
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * An item with a test to see if any item is that item.
+ */
+public interface TestableEntity {
+    /**
+     * If an Entity matches the test.
+     *
+     * @param entity The entity to test.
+     * @return If the entity matches.
+     */
+    boolean matches(@Nullable Entity entity);
+
+    /**
+     * Spawn the entity.
+     *
+     * @param location The location.
+     * @return The entity.
+     */
+    Entity spawn(@NotNull Location location);
+}

eco-api/src/main/java/com/willfp/eco/core/entities/args/EntityArgParseResult.java

@@ -0,0 +1,33 @@
+package com.willfp.eco.core.entities.args;
+
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.function.Consumer;
+import java.util.function.Predicate;
+
+/**
+ * @param test     The test for the entity.
+ * @param modifier The modifier to apply to the entity.
+ * @see EntityArgParser
+ */
+public record EntityArgParseResult(@NotNull Predicate<Entity> test,
+                                   @NotNull Consumer<Entity> modifier) {
+    /**
+     * Kotlin destructuring support.
+     *
+     * @return The test.
+     */
+    public Predicate<Entity> component1() {
+        return test;
+    }
+
+    /**
+     * Kotlin destructuring support.
+     *
+     * @return The modifier.
+     */
+    public Consumer<Entity> component2() {
+        return modifier;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/args/EntityArgParser.java

@@ -0,0 +1,20 @@
+package com.willfp.eco.core.entities.args;
+
+import com.willfp.eco.core.entities.TestableEntity;
+import org.bukkit.Location;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * An argument parser should generate the predicate as well
+ * as modify the Entity for {@link TestableEntity#spawn(Location)}.
+ */
+public interface EntityArgParser {
+    /**
+     * Parse the arguments.
+     *
+     * @param args The arguments.
+     * @return The predicate test to apply to the modified entity.
+     */
+    @Nullable EntityArgParseResult parseArguments(@NotNull String[] args);
+}

eco-api/src/main/java/com/willfp/eco/core/entities/impl/EmptyTestableEntity.java

@@ -0,0 +1,33 @@
+package com.willfp.eco.core.entities.impl;
+
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.entities.TestableEntity;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Empty entity.
+ */
+public class EmptyTestableEntity implements TestableEntity {
+    /**
+     * Create a new empty testable entity.
+     */
+    public EmptyTestableEntity() {
+
+    }
+
+    @Override
+    public boolean matches(@Nullable final Entity entity) {
+        return false;
+    }
+
+    @Override
+    public Entity spawn(@NotNull final Location location) {
+        Validate.notNull(location.getWorld());
+
+        return Eco.getHandler().createDummyEntity(location);
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/impl/ModifiedTestableEntity.java

@@ -0,0 +1,69 @@
+package com.willfp.eco.core.entities.impl;
+
+import com.willfp.eco.core.entities.TestableEntity;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Function;
+import java.util.function.Predicate;
+
+/**
+ * Existing testable entity with an extra filter.
+ *
+ * @see com.willfp.eco.core.entities.CustomEntity
+ */
+public class ModifiedTestableEntity implements TestableEntity {
+    /**
+     * The item.
+     */
+    private final TestableEntity handle;
+
+    /**
+     * The amount.
+     */
+    private final Predicate<Entity> test;
+
+    /**
+     * The provider to spawn the entity.
+     */
+    private final Function<Location, Entity> provider;
+
+    /**
+     * Create a new modified testable entity.
+     *
+     * @param entity   The base entity.
+     * @param test     The test.
+     * @param provider The provider to spawn the entity.
+     */
+    public ModifiedTestableEntity(@NotNull final TestableEntity entity,
+                                  @NotNull final Predicate<@NotNull Entity> test,
+                                  @NotNull final Function<Location, Entity> provider) {
+        this.handle = entity;
+        this.test = test;
+        this.provider = provider;
+    }
+
+    @Override
+    public boolean matches(@Nullable final Entity entity) {
+        return entity != null && handle.matches(entity) && test.test(entity);
+    }
+
+    @Override
+    public Entity spawn(@NotNull final Location location) {
+        Validate.notNull(location.getWorld());
+
+        return provider.apply(location);
+    }
+
+    /**
+     * Get the handle.
+     *
+     * @return The handle.
+     */
+    public TestableEntity getHandle() {
+        return this.handle;
+    }
+}

eco-api/src/main/java/com/willfp/eco/core/entities/impl/SimpleTestableEntity.java

@@ -0,0 +1,53 @@
+package com.willfp.eco.core.entities.impl;
+
+import com.willfp.eco.core.entities.TestableEntity;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.EntityType;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Default vanilla entities.
+ */
+public class SimpleTestableEntity implements TestableEntity {
+    /**
+     * The entity type.
+     */
+    private final EntityType type;
+
+    /**
+     * Create a new simple testable entity.
+     *
+     * @param type The entity type.
+     */
+    public SimpleTestableEntity(@NotNull final EntityType type) {
+        this.type = type;
+
+        Validate.notNull(type.getEntityClass(), "Entity cannot be of unknown type!");
+    }
+
+    @Override
+    public boolean matches(@Nullable final Entity entity) {
+        return entity != null && entity.getType() == type;
+    }
+
+    @Override
+    public Entity spawn(@NotNull final Location location) {
+        Validate.notNull(location.getWorld());
+
+        assert type.getEntityClass() != null;
+
+        return location.getWorld().spawn(location, type.getEntityClass());
+    }
+
+    /**
+     * Get the type.
+     *
+     * @return The type.
+     */
+    public EntityType getType() {
+        return this.type;
+    }
+}

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

@@ -1,15 +1,19 @@
 package com.willfp.eco.core.gui;
 
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.gui.menu.MenuBuilder;
 import com.willfp.eco.core.gui.slot.SlotBuilder;
 import com.willfp.eco.core.gui.slot.functional.SlotProvider;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Internal component used by {@link com.willfp.eco.core.gui.menu.Menu#builder(int)}
  * and {@link com.willfp.eco.core.gui.slot.Slot#builder(ItemStack)}.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface GUIFactory {
     /**
      * Create slot builder.

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

@@ -0,0 +1,40 @@
+package com.willfp.eco.core.integrations.customentities;
+
+import org.jetbrains.annotations.NotNull;
+
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * Class to handle custom entity integrations.
+ */
+public final class CustomEntitiesManager {
+    /**
+     * A set of all registered integrations.
+     */
+    private static final Set<CustomEntitiesWrapper> REGISTERED = new HashSet<>();
+
+    /**
+     * Register a new integration.
+     *
+     * @param integration The integration to register.
+     */
+    public static void register(@NotNull final CustomEntitiesWrapper integration) {
+        REGISTERED.add(integration);
+    }
+
+    /**
+     * Register all the custom entities for a specific plugin into eco.
+     *
+     * @see com.willfp.eco.core.entities.Entities
+     */
+    public static void registerAllEntities() {
+        for (CustomEntitiesWrapper wrapper : REGISTERED) {
+            wrapper.registerAllEntities();
+        }
+    }
+
+    private CustomEntitiesManager() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

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

@@ -0,0 +1,15 @@
+package com.willfp.eco.core.integrations.customentities;
+
+import com.willfp.eco.core.integrations.Integration;
+
+/**
+ * Wrapper class for custom item integrations.
+ */
+public interface CustomEntitiesWrapper extends Integration {
+    /**
+     * Register all the custom entities for a specific plugin into eco.
+     *
+     * @see com.willfp.eco.core.entities.Entities
+     */
+    void registerAllEntities();
+}

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

@@ -1,10 +1,12 @@
 package com.willfp.eco.core.integrations.placeholder;
 
+import com.willfp.eco.core.EcoPlugin;
 import org.apache.commons.lang.Validate;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.Objects;
 import java.util.function.Function;
 
 /**
@@ -28,12 +30,20 @@ public class PlaceholderEntry {
      */
     private final boolean requiresPlayer;
 
+    /**
+     * The plugin for the placeholder.
+     */
+    @Nullable
+    private final EcoPlugin plugin;
+
     /**
      * Create a placeholder entry that doesn't require a player.
      *
      * @param identifier The identifier of the placeholder.
      * @param function   A lambda to get the result of the placeholder given a player.
+     * @deprecated Specify a plugin.
      */
+    @Deprecated
     public PlaceholderEntry(@NotNull final String identifier,
                             @NotNull final Function<Player, String> function) {
         this(identifier, function, false);
@@ -45,10 +55,41 @@ public class PlaceholderEntry {
      * @param identifier     The identifier of the placeholder.
      * @param function       A lambda to get the result of the placeholder.
      * @param requiresPlayer If the placeholder requires a player.
+     * @deprecated Specify a plugin.
      */
+    @Deprecated
     public PlaceholderEntry(@NotNull final String identifier,
                             @NotNull final Function<Player, String> function,
                             final boolean requiresPlayer) {
+        this(null, identifier, function, requiresPlayer);
+    }
+
+    /**
+     * Create a placeholder entry that doesn't require a player.
+     *
+     * @param plugin     The plugin for the placeholder.
+     * @param identifier The identifier of the placeholder.
+     * @param function   A lambda to get the result of the placeholder given a player.
+     */
+    public PlaceholderEntry(@Nullable final EcoPlugin plugin,
+                            @NotNull final String identifier,
+                            @NotNull final Function<Player, String> function) {
+        this(plugin, identifier, function, false);
+    }
+
+    /**
+     * Create a placeholder entry that may require a player.
+     *
+     * @param plugin         The plugin for the placeholder.
+     * @param identifier     The identifier of the placeholder.
+     * @param function       A lambda to get the result of the placeholder.
+     * @param requiresPlayer If the placeholder requires a player.
+     */
+    public PlaceholderEntry(@Nullable final EcoPlugin plugin,
+                            @NotNull final String identifier,
+                            @NotNull final Function<Player, String> function,
+                            final boolean requiresPlayer) {
+        this.plugin = plugin;
         this.identifier = identifier;
         this.function = function;
         this.requiresPlayer = requiresPlayer;
@@ -85,10 +126,37 @@ public class PlaceholderEntry {
         return identifier;
     }
 
+    /**
+     * Get the plugin.
+     *
+     * @return The plugin.
+     */
+    @Nullable
+    public EcoPlugin getPlugin() {
+        return plugin;
+    }
+
     /**
      * Register the placeholder.
      */
     public void register() {
         PlaceholderManager.registerPlaceholder(this);
     }
+
+    @Override
+    public boolean equals(@Nullable final Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof PlaceholderEntry entry)) {
+            return false;
+        }
+        return Objects.equals(this.getIdentifier(), entry.getIdentifier())
+                && Objects.equals(this.getPlugin(), entry.getPlugin());
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(this.getIdentifier(), this.getPlugin());
+    }
 }

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

@@ -5,6 +5,9 @@ import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * Wrapper class for placeholder integrations.
  */
@@ -24,4 +27,14 @@ public interface PlaceholderIntegration extends Integration {
      */
     String translate(@NotNull String text,
                      @Nullable Player player);
+
+    /**
+     * Find all placeholders in a given text.
+     *
+     * @param text The text.
+     * @return The placeholders.
+     */
+    default List<String> findPlaceholdersIn(@NotNull String text) {
+        return new ArrayList<>();
+    }
 }

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

@@ -1,13 +1,20 @@
 package com.willfp.eco.core.integrations.placeholder;
 
+import com.github.benmanes.caffeine.cache.Caffeine;
+import com.github.benmanes.caffeine.cache.LoadingCache;
+import com.willfp.eco.core.Eco;
+import com.willfp.eco.core.EcoPlugin;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.concurrent.TimeUnit;
 
 /**
  * Class to handle placeholder integrations.
@@ -16,17 +23,24 @@ public final class PlaceholderManager {
     /**
      * All registered placeholders.
      */
-    private static final Map<String, PlaceholderEntry> REGISTERED_PLACEHOLDERS = new HashMap<>();
+    private static final Map<EcoPlugin, Map<String, PlaceholderEntry>> REGISTERED_PLACEHOLDERS = new HashMap<>();
 
     /**
      * All registered placeholder integrations.
      */
     private static final Set<PlaceholderIntegration> REGISTERED_INTEGRATIONS = new HashSet<>();
 
+    /**
+     * Placeholder Cache.
+     */
+    private static final LoadingCache<EntryWithPlayer, String> PLACEHOLDER_CACHE = Caffeine.newBuilder()
+            .expireAfterWrite(50, TimeUnit.MILLISECONDS)
+            .build(key -> key.entry.getResult(key.player));
+
     /**
      * Register a new placeholder integration.
      *
-     * @param integration The {@link PlaceholderIntegration} to register.
+     * @param integration The {@link com.willfp.eco.core.integrations.placeholder.PlaceholderIntegration} to register.
      */
     public static void addIntegration(@NotNull final PlaceholderIntegration integration) {
         integration.registerIntegration();
@@ -36,11 +50,14 @@ public final class PlaceholderManager {
     /**
      * Register a placeholder.
      *
-     * @param expansion The {@link PlaceholderEntry} to register.
+     * @param expansion The {@link com.willfp.eco.core.integrations.placeholder.PlaceholderEntry} to register.
      */
     public static void registerPlaceholder(@NotNull final PlaceholderEntry expansion) {
-        REGISTERED_PLACEHOLDERS.remove(expansion.getIdentifier());
-        REGISTERED_PLACEHOLDERS.put(expansion.getIdentifier(), expansion);
+        EcoPlugin plugin = expansion.getPlugin() == null ? Eco.getHandler().getEcoPlugin() : expansion.getPlugin();
+        Map<String, PlaceholderEntry> pluginPlaceholders = REGISTERED_PLACEHOLDERS
+                .getOrDefault(plugin, new HashMap<>());
+        pluginPlaceholders.put(expansion.getIdentifier(), expansion);
+        REGISTERED_PLACEHOLDERS.put(plugin, pluginPlaceholders);
     }
 
     /**
@@ -49,10 +66,36 @@ public final class PlaceholderManager {
      * @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.
      */
+    @Deprecated
     public static String getResult(@Nullable final Player player,
                                    @NotNull final String identifier) {
-        PlaceholderEntry entry = REGISTERED_PLACEHOLDERS.get(identifier.toLowerCase());
+        return getResult(player, identifier, null);
+    }
+
+    /**
+     * 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.
+     */
+    public static String getResult(@Nullable final Player player,
+                                   @NotNull final String identifier,
+                                   @Nullable final EcoPlugin plugin) {
+        EcoPlugin owner = plugin == null ? Eco.getHandler().getEcoPlugin() : plugin;
+        PlaceholderEntry entry = REGISTERED_PLACEHOLDERS.getOrDefault(owner, new HashMap<>()).get(identifier.toLowerCase());
+
+        if (entry == null && plugin != null) {
+            PlaceholderEntry alternate = REGISTERED_PLACEHOLDERS.getOrDefault(Eco.getHandler().getEcoPlugin(), new HashMap<>())
+                    .get(identifier.toLowerCase());
+            if (alternate != null) {
+                entry = alternate;
+            }
+        }
+
         if (entry == null) {
             return "";
         }
@@ -61,7 +104,7 @@ public final class PlaceholderManager {
             return "";
         }
 
-        return entry.getResult(player);
+        return PLACEHOLDER_CACHE.get(new EntryWithPlayer(entry, player));
     }
 
     /**
@@ -80,6 +123,26 @@ public final class PlaceholderManager {
         return processed;
     }
 
+    /**
+     * Find all placeholders in a given text.
+     *
+     * @param text The text.
+     * @return The placeholders.
+     */
+    public static List<String> findPlaceholdersIn(@NotNull final String text) {
+        List<String> found = new ArrayList<>();
+        for (PlaceholderIntegration integration : REGISTERED_INTEGRATIONS) {
+            found.addAll(integration.findPlaceholdersIn(text));
+        }
+
+        return found;
+    }
+
+    private static record EntryWithPlayer(@NotNull PlaceholderEntry entry,
+                                          @Nullable Player player) {
+
+    }
+
     private PlaceholderManager() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }

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

@@ -66,7 +66,7 @@ public class CustomItem implements TestableItem {
 
     @Override
     public ItemStack getItem() {
-        return item;
+        return item.clone();
     }
 
     /**

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

@@ -0,0 +1,103 @@
+package com.willfp.eco.core.items;
+
+import com.willfp.eco.core.fast.FastItemStack;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * An item and its {@link com.willfp.eco.core.fast.FastItemStack} hash.
+ */
+public final class HashedItem {
+    /**
+     * The item.
+     */
+    private final ItemStack item;
+
+    /**
+     * The hash.
+     */
+    private final int hash;
+
+    /**
+     * Create new hashed item.
+     *
+     * @param item The item.
+     * @param hash The hash.
+     */
+    private HashedItem(@NotNull final ItemStack item,
+                       final int hash) {
+        this.item = item;
+        this.hash = hash;
+    }
+
+    /**
+     * Get the item.
+     *
+     * @return The ItemStack.
+     */
+    public ItemStack getItem() {
+        return this.item;
+    }
+
+    /**
+     * Get the hash.
+     *
+     * @return The hash.
+     */
+    public int getHash() {
+        return this.hash;
+    }
+
+    /**
+     * Kotlin destructuring support.
+     *
+     * @return The ItemStack.
+     */
+    public ItemStack component1() {
+        return this.getItem();
+    }
+
+    /**
+     * Kotlin destructuring support.
+     *
+     * @return The hash.
+     */
+    public int component2() {
+        return this.getHash();
+    }
+
+    @Override
+    public int hashCode() {
+        return this.hash;
+    }
+
+    @Override
+    public boolean equals(@Nullable final Object other) {
+        if (!(other instanceof HashedItem o)) {
+            return false;
+        }
+
+        return o.hash == this.hash;
+    }
+
+    /**
+     * Hashed item from an item.
+     *
+     * @param item The item.
+     * @return The hashed item.
+     */
+    public static HashedItem of(@NotNull final ItemStack item) {
+        return new HashedItem(item, FastItemStack.wrap(item).hashCode());
+    }
+
+    /**
+     * Hashed item from a fast item stack.
+     *
+     * @param item The item.
+     * @return The hashed item.
+     */
+    public static HashedItem of(@NotNull final FastItemStack item) {
+        return new HashedItem(item.unwrap(), item.hashCode());
+    }
+}

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

@@ -1,5 +1,7 @@
 package com.willfp.eco.core.items;
 
+import com.github.benmanes.caffeine.cache.Caffeine;
+import com.github.benmanes.caffeine.cache.LoadingCache;
 import com.willfp.eco.core.items.args.LookupArgParser;
 import com.willfp.eco.core.items.provider.ItemProvider;
 import com.willfp.eco.core.recipe.parts.EmptyTestableItem;
@@ -8,6 +10,7 @@ import com.willfp.eco.core.recipe.parts.ModifiedTestableItem;
 import com.willfp.eco.core.recipe.parts.TestableStack;
 import com.willfp.eco.util.NamespacedKeyUtils;
 import com.willfp.eco.util.NumberUtils;
+import com.willfp.eco.util.StringUtils;
 import org.bukkit.Material;
 import org.bukkit.NamespacedKey;
 import org.bukkit.inventory.ItemStack;
@@ -19,8 +22,10 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.TimeUnit;
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
@@ -33,6 +38,25 @@ public final class Items {
      */
     private static final Map<NamespacedKey, TestableItem> REGISTRY = new ConcurrentHashMap<>();
 
+    /**
+     * Cached custom item lookups, using {@link HashedItem}.
+     */
+    private static final LoadingCache<HashedItem, Optional<TestableItem>> CACHE = Caffeine.newBuilder()
+            .expireAfterAccess(5, TimeUnit.MINUTES)
+            .build(
+                    key -> {
+                        TestableItem match = null;
+                        for (TestableItem item : REGISTRY.values()) {
+                            if (item.matches(key.getItem())) {
+                                match = item;
+                                break;
+                            }
+                        }
+
+                        return Optional.ofNullable(match);
+                    }
+            );
+
     /**
      * All item providers.
      */
@@ -118,7 +142,8 @@ public final class Items {
             return new EmptyTestableItem();
         }
 
-        String[] args = key.split(" ");
+        String[] args = StringUtils.parseTokens(key);
+
         if (args.length == 0) {
             return new EmptyTestableItem();
         }
@@ -192,7 +217,7 @@ public final class Items {
             }
         }
 
-        // Marked as redundant but i am covering all bases here
+        // Marked as redundant but I am covering all bases here
         if (item == null || item instanceof EmptyTestableItem) {
             return new EmptyTestableItem();
         }
@@ -274,12 +299,7 @@ public final class Items {
      * @return If is recipe.
      */
     public static boolean isCustomItem(@NotNull final ItemStack itemStack) {
-        for (TestableItem item : REGISTRY.values()) {
-            if (item.matches(itemStack)) {
-                return true;
-            }
-        }
-        return false;
+        return getCustomItem(itemStack) != null;
     }
 
     /**
@@ -290,12 +310,7 @@ public final class Items {
      */
     @Nullable
     public static CustomItem getCustomItem(@NotNull final ItemStack itemStack) {
-        for (TestableItem item : REGISTRY.values()) {
-            if (item.matches(itemStack)) {
-                return getOrWrap(item);
-            }
-        }
-        return null;
+        return CACHE.get(HashedItem.of(itemStack)).map(Items::getOrWrap).orElse(null);
     }
 
     /**

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

@@ -1,30 +0,0 @@
-package com.willfp.eco.core.items.args;
-
-import org.bukkit.Bukkit;
-import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.meta.ItemMeta;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
-import java.util.function.Predicate;
-
-/**
- * Parse leather armor colors.
- *
- * @deprecated Moved to internals.
- */
-@Deprecated(since = "6.16.0", forRemoval = true)
-public class ColorArgParser implements LookupArgParser {
-    /**
-     * Instantiate arg parser.
-     */
-    public ColorArgParser() {
-        Bukkit.getLogger().severe("Instantiation of class marked for removal! (" + this.getClass().getName() + "), this will throw an error in a future release!");
-    }
-
-    @Override
-    public @Nullable Predicate<ItemStack> parseArguments(@NotNull final String[] args,
-                                                         @NotNull final ItemMeta meta) {
-        return null;
-    }
-}

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

@@ -1,30 +0,0 @@
-package com.willfp.eco.core.items.args;
-
-import org.bukkit.Bukkit;
-import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.meta.ItemMeta;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
-import java.util.function.Predicate;
-
-/**
- * Parse custom model data.
- *
- * @deprecated Moved to internals.
- */
-@Deprecated(since = "6.16.0", forRemoval = true)
-public class CustomModelDataArgParser implements LookupArgParser {
-    /**
-     * Instantiate arg parser.
-     */
-    public CustomModelDataArgParser() {
-        Bukkit.getLogger().severe("Instantiation of class marked for removal! (" + this.getClass().getName() + "), this will throw an error in a future release!");
-    }
-
-    @Override
-    public @Nullable Predicate<ItemStack> parseArguments(@NotNull final String[] args,
-                                                         @NotNull final ItemMeta meta) {
-        return null;
-    }
-}

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

@@ -1,30 +0,0 @@
-package com.willfp.eco.core.items.args;
-
-import org.bukkit.Bukkit;
-import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.meta.ItemMeta;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
-import java.util.function.Predicate;
-
-/**
- * Parses enchantment arguments.
- *
- * @deprecated Moved to internals.
- */
-@Deprecated(since = "6.16.0", forRemoval = true)
-public class EnchantmentArgParser implements LookupArgParser {
-    /**
-     * Instantiate arg parser.
-     */
-    public EnchantmentArgParser() {
-        Bukkit.getLogger().severe("Instantiation of class marked for removal! (" + this.getClass().getName() + "), this will throw an error in a future release!");
-    }
-
-    @Override
-    public @Nullable Predicate<ItemStack> parseArguments(@NotNull final String[] args,
-                                                         @NotNull final ItemMeta meta) {
-        return null;
-    }
-}

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

@@ -1,30 +0,0 @@
-package com.willfp.eco.core.items.args;
-
-import org.bukkit.Bukkit;
-import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.meta.ItemMeta;
-import org.jetbrains.annotations.NotNull;
-import org.jetbrains.annotations.Nullable;
-
-import java.util.function.Predicate;
-
-/**
- * Parse skull textures.
- *
- * @deprecated Moved to internals.
- */
-@Deprecated(since = "6.16.0", forRemoval = true)
-public class TextureArgParser implements LookupArgParser {
-    /**
-     * Instantiate arg parser.
-     */
-    public TextureArgParser() {
-        Bukkit.getLogger().severe("Instantiation of class marked for removal! (" + this.getClass().getName() + "), this will throw an error in a future release!");
-    }
-
-    @Override
-    public @Nullable Predicate<ItemStack> parseArguments(@NotNull final String[] args,
-                                                         @NotNull final ItemMeta meta) {
-        return null;
-    }
-}

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

@@ -39,7 +39,7 @@ public class EnchantedBookBuilder extends AbstractItemStackBuilder<EnchantmentSt
      * @return The builder.
      */
     public EnchantedBookBuilder addStoredEnchantment(@NotNull final Supplier<Enchantment> enchantment,
-                                                     final Supplier<Integer> level) {
+                                                     @NotNull final Supplier<Integer> level) {
         return this.addStoredEnchantment(enchantment.get(), level.get());
     }
 }

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

@@ -6,6 +6,8 @@ import com.willfp.eco.core.EcoPlugin;
 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;
@@ -58,7 +60,10 @@ public final class Recipes {
         }
 
         if (key.getKey().contains("_displayed")) {
-            NamespacedKey otherKey = new NamespacedKey(key.getNamespace(), key.getKey().replace("_displayed", ""));
+            NamespacedKey otherKey = NamespacedKeyUtils.create(
+                    key.getNamespace(),
+                    key.getKey().replace("_displayed", "")
+            );
 
             return RECIPES.get(otherKey);
         }
@@ -92,6 +97,7 @@ public final class Recipes {
      * @param permission    The permission.
      * @return The recipe.
      */
+    @Nullable
     public static CraftingRecipe createAndRegisterRecipe(@NotNull final EcoPlugin plugin,
                                                          @NotNull final String key,
                                                          @NotNull final ItemStack output,
@@ -105,6 +111,12 @@ public final class Recipes {
             builder.setRecipePart(i, Items.lookup(recipeStrings.get(i)));
         }
 
+        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.");
+            return null;
+        }
+
         ShapedCraftingRecipe recipe = builder.build();
         recipe.register();
 

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

@@ -111,7 +111,7 @@ public final class ShapedCraftingRecipe extends PluginDependent<EcoPlugin> imple
                 List<String> lore = meta.hasLore() ? meta.getLore() : new ArrayList<>();
                 assert lore != null;
                 lore.add("");
-                String add = Eco.getHandler().getEcoPlugin().getLangYml().getString("multiple-in-craft");
+                String add = Eco.getHandler().getEcoPlugin().getLangYml().getFormattedString("multiple-in-craft");
                 add = add.replace("%amount%", String.valueOf(item.getAmount()));
                 lore.add(add);
                 meta.setLore(lore);
@@ -287,6 +287,20 @@ public final class ShapedCraftingRecipe extends PluginDependent<EcoPlugin> imple
             return this;
         }
 
+        /**
+         * Check if recipe parts are all air.
+         *
+         * @return If recipe parts are all air.
+         */
+        public boolean isAir() {
+            for (TestableItem recipePart : this.recipeParts) {
+                if (recipePart!= null && !(recipePart instanceof EmptyTestableItem)) {
+                    return false;
+                }
+            }
+            return true;
+        }
+
         /**
          * Build the recipe.
          *

eco-api/src/main/java/com/willfp/eco/core/requirement/RequirementFactory.java

@@ -1,10 +1,14 @@
 package com.willfp.eco.core.requirement;
 
+import com.willfp.eco.core.Eco;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
 /**
  * Interface for internal requirement factory implementations.
  */
+@ApiStatus.Internal
+@Eco.HandlerComponent
 public interface RequirementFactory {
     /**
      * Create a requirement.

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

@@ -92,7 +92,7 @@ public class Paste {
             conn.setRequestMethod("GET");
             try (var reader = new BufferedReader(
                     new InputStreamReader(conn.getInputStream()))) {
-                for (String line; (line = reader.readLine()) != null; ) {
+                for (String line; (line = reader.readLine()) != null;) {
                     result.append(line);
                 }
             }

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

@@ -91,6 +91,24 @@ public final class ListUtils {
         return index >= 0 && index < list.size() ? list.get(index) : null;
     }
 
+    /**
+     * Get if an iterable of strings contains a certain element regardless of case.
+     *
+     * @param list    The list.
+     * @param element The element.
+     * @return If contained.
+     */
+    public static boolean containsIgnoreCase(@NotNull final Iterable<String> list,
+                                             @NotNull final String element) {
+        for (String s : list) {
+            if (s.equalsIgnoreCase(element)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     private ListUtils() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }

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

@@ -1,10 +1,9 @@
 package com.willfp.eco.util;
 
+import com.willfp.eco.core.Eco;
 import org.bukkit.NamespacedKey;
 import org.jetbrains.annotations.NotNull;
 
-import java.util.Objects;
-
 /**
  * Utilities / API methods for {@link NamespacedKey}s.
  */
@@ -17,7 +16,7 @@ public final class NamespacedKeyUtils {
      */
     @NotNull
     public static NamespacedKey createEcoKey(@NotNull final String string) {
-        return Objects.requireNonNull(NamespacedKey.fromString("eco:" + string));
+        return NamespacedKeyUtils.create("eco", string);
     }
 
     /**
@@ -30,7 +29,28 @@ public final class NamespacedKeyUtils {
     @NotNull
     public static NamespacedKey create(@NotNull final String namespace,
                                        @NotNull final String key) {
-        return Objects.requireNonNull(NamespacedKey.fromString(namespace + ":" + key));
+        return Eco.getHandler().createNamespacedKey(
+                namespace,
+                key
+        );
+    }
+
+    /**
+     * Create a NamespacedKey from a string.
+     * <p>
+     * Preferred over {@link NamespacedKey#fromString(String)} for performance reasons.
+     *
+     * @param string The string.
+     * @return The key.
+     */
+    @NotNull
+    public static NamespacedKey fromString(@NotNull final String string) {
+        int index = string.indexOf(":");
+
+        return NamespacedKeyUtils.create(
+                string.substring(0, index),
+                string.substring(index + 1)
+        );
     }
 
     private NamespacedKeyUtils() {

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

@@ -1,11 +1,16 @@
 package com.willfp.eco.util;
 
+import org.apache.commons.lang.Validate;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.text.DecimalFormat;
 import java.util.Map;
 import java.util.TreeMap;
 import java.util.concurrent.ThreadLocalRandom;
+import java.util.function.BiFunction;
 
 /**
  * Utilities / API methods for numbers.
@@ -16,6 +21,11 @@ public final class NumberUtils {
      */
     private static final double[] SIN_LOOKUP = new double[65536];
 
+    /**
+     * Crunch handler.
+     */
+    private static BiFunction<String, Player, Double> crunch = null;
+
     /**
      * Set of roman numerals to look up.
      */
@@ -83,7 +93,9 @@ public final class NumberUtils {
      * @param toChange The value to test.
      * @param limit    The maximum.
      * @return The new value.
+     * @deprecated Pointless method.
      */
+    @Deprecated(since = "6.19.0")
     public static int equalIfOver(final int toChange,
                                   final int limit) {
         return Math.min(toChange, limit);
@@ -95,7 +107,9 @@ public final class NumberUtils {
      * @param toChange The value to test.
      * @param limit    The maximum.
      * @return The new value.
+     * @deprecated Pointless method.
      */
+    @Deprecated(since = "6.19.0")
     public static double equalIfOver(final double toChange,
                                      final double limit) {
         return Math.min(toChange, limit);
@@ -185,11 +199,23 @@ public final class NumberUtils {
     /**
      * Get Log base 2 of a number.
      *
-     * @param toLog The number.
+     * @param a The number.
      * @return The result.
      */
-    public static int log2(final int toLog) {
-        return (int) (Math.log(toLog) / Math.log(2));
+    public static int log2(final int a) {
+        return (int) logBase(a, 2);
+    }
+
+    /**
+     * Log with a base.
+     *
+     * @param a    The number.
+     * @param base The base.
+     * @return The logarithm.
+     */
+    public static double logBase(final double a,
+                                 final double base) {
+        return Math.log(a) / Math.log(base);
     }
 
     /**
@@ -206,6 +232,39 @@ public final class NumberUtils {
         return formatted.endsWith("00") ? String.valueOf((int) toFormat) : formatted;
     }
 
+    /**
+     * Evaluate an expression.
+     *
+     * @param expression The expression.
+     * @return The value of the expression, or zero if invalid.
+     */
+    public static double evaluateExpression(@NotNull final String expression) {
+        return evaluateExpression(expression, null);
+    }
+
+    /**
+     * Evaluate an expression with respect to a player (for placeholders).
+     *
+     * @param expression The expression.
+     * @param player     The player.
+     * @return The value of the expression, or zero if invalid.
+     */
+    public static double evaluateExpression(@NotNull final String expression,
+                                            @Nullable final Player player) {
+        return crunch.apply(expression, player);
+    }
+
+    /**
+     * Init crunch handler.
+     *
+     * @param handler The handler.
+     */
+    @ApiStatus.Internal
+    public static void initCrunch(@NotNull final BiFunction<String, Player, Double> handler) {
+        Validate.isTrue(crunch == null, "Already initialized!");
+        crunch = handler;
+    }
+
     private NumberUtils() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }

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

@@ -1,7 +1,10 @@
 package com.willfp.eco.util;
 
+import com.github.benmanes.caffeine.cache.Caffeine;
+import com.github.benmanes.caffeine.cache.LoadingCache;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.gson.JsonSyntaxException;
 import com.willfp.eco.core.Prerequisite;
 import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
 import net.kyori.adventure.text.Component;
@@ -19,6 +22,7 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.TimeUnit;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
@@ -58,6 +62,49 @@ public final class StringUtils {
             .hexColors()
             .build();
 
+    /**
+     * GSON serializer.
+     */
+    private static final GsonComponentSerializer GSON_COMPONENT_SERIALIZER = GsonComponentSerializer.builder()
+            .emitLegacyHoverEvent()
+            .build();
+
+    /**
+     * String format cache.
+     */
+    private static final LoadingCache<String, String> STRING_FORMAT_CACHE = Caffeine.newBuilder()
+            .expireAfterAccess(10, TimeUnit.SECONDS)
+            .build(StringUtils::processFormatting);
+
+    /**
+     * Json -> Legacy Cache.
+     */
+    private static final LoadingCache<String, String> JSON_TO_LEGACY = Caffeine.newBuilder()
+            .expireAfterAccess(10, TimeUnit.SECONDS)
+            .build(
+                    json -> {
+                        try {
+                            Component component = GSON_COMPONENT_SERIALIZER.deserialize(json);
+                            return LEGACY_COMPONENT_SERIALIZER.serialize(component);
+                        } catch (JsonSyntaxException e) {
+                            return json;
+                        }
+                    }
+            );
+
+    /**
+     * Legacy -> Json Cache.
+     */
+    private static final LoadingCache<String, String> LEGACY_TO_JSON = Caffeine.newBuilder()
+            .expireAfterAccess(10, TimeUnit.SECONDS)
+            .build(
+                    legacy -> GSON_COMPONENT_SERIALIZER.serialize(
+                            Component.empty().decoration(TextDecoration.ITALIC, false).append(
+                                    LEGACY_COMPONENT_SERIALIZER.deserialize(legacy)
+                            )
+                    )
+            );
+
     /**
      * Color map.
      */
@@ -264,6 +311,11 @@ public final class StringUtils {
         if (option == FormatOption.WITH_PLACEHOLDERS) {
             processedMessage = PlaceholderManager.translatePlaceholders(processedMessage, player);
         }
+        return STRING_FORMAT_CACHE.get(processedMessage);
+    }
+
+    private static String processFormatting(@NotNull final String message) {
+        String processedMessage = message;
         processedMessage = ChatColor.translateAlternateColorCodes('&', processedMessage);
         processedMessage = translateGradients(processedMessage);
         processedMessage = translateHexColorCodes(processedMessage);
@@ -415,11 +467,8 @@ public final class StringUtils {
         if (legacy == null) {
             processed = "";
         }
-        return GsonComponentSerializer.gson().serialize(
-                Component.empty().decoration(TextDecoration.ITALIC, false).append(
-                        LEGACY_COMPONENT_SERIALIZER.deserialize(processed)
-                )
-        );
+
+        return LEGACY_TO_JSON.get(processed);
     }
 
     /**
@@ -429,10 +478,12 @@ public final class StringUtils {
      * @return The legacy string.
      */
     @NotNull
-    public static String jsonToLegacy(@NotNull final String json) {
-        return LEGACY_COMPONENT_SERIALIZER.serialize(
-                GsonComponentSerializer.gson().deserialize(json)
-        );
+    public static String jsonToLegacy(@Nullable final String json) {
+        if (json == null || json.isEmpty()) {
+            return "";
+        }
+
+        return JSON_TO_LEGACY.get(json);
     }
 
     /**
@@ -462,6 +513,53 @@ public final class StringUtils {
         return LEGACY_COMPONENT_SERIALIZER.serialize(component);
     }
 
+    /**
+     * Parse string into tokens.
+     * <p>
+     * Handles quoted strings for names.
+     *
+     * @param lookup The lookup string.
+     * @return An array of tokens to be processed.
+     * @author Shawn (https://stackoverflow.com/questions/70606170/split-a-list-on-spaces-and-group-quoted-characters/70606653#70606653)
+     */
+    @NotNull
+    public static String[] parseTokens(@NotNull final String lookup) {
+        char[] chars = lookup.toCharArray();
+        List<String> tokens = new ArrayList<>();
+        StringBuilder tokenBuilder = new StringBuilder();
+        for (int i = 0; i < chars.length; i++) {
+            if (chars[i] == ' ') {
+                /*
+                Take the current value of the argument builder, append it to the
+                list of found tokens, and then clear it for the next argument.
+                 */
+                tokens.add(tokenBuilder.toString());
+                tokenBuilder.setLength(0);
+            } else if (chars[i] == '"') {
+                /*
+                Work until the next unescaped quote to handle quotes with
+                spaces in them - assumes the input string is well-formatted
+                 */
+                for (i++; chars[i] != '"'; i++) {
+                    /*
+                    If the found quote is escaped, ignore it in the parsing
+                     */
+                    if (chars[i] == '\\') {
+                        i++;
+                    }
+                    tokenBuilder.append(chars[i]);
+                }
+            } else {
+                /*
+                If it's a regular character, just append it to the current argument.
+                 */
+                tokenBuilder.append(chars[i]);
+            }
+        }
+        tokens.add(tokenBuilder.toString()); // Adds the last argument to the tokens.
+        return tokens.toArray(new String[0]);
+    }
+
     /**
      * Options for formatting.
      */

eco-api/src/main/kotlin/com/willfp/eco/core/data/Profiles.kt

@@ -0,0 +1,18 @@
+@file:JvmName("ProfileExtensions")
+
+package com.willfp.eco.core.data
+
+import org.bukkit.OfflinePlayer
+import org.bukkit.Server
+
+/**
+ * @see PlayerProfile.load
+ */
+val OfflinePlayer.profile: PlayerProfile
+    get() = PlayerProfile.load(this)
+
+/**
+ * @see ServerProfile.load
+ */
+val Server.profile: ServerProfile
+    get() = ServerProfile.load()

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

@@ -0,0 +1,11 @@
+@file:JvmName("FastItemStackExtensions")
+
+package com.willfp.eco.core.fast
+
+import org.bukkit.inventory.ItemStack
+
+/**
+ * @see FastItemStack.wrap
+ */
+fun ItemStack.fast(): FastItemStack =
+    FastItemStack.wrap(this)

eco-api/src/main/kotlin/com/willfp/eco/core/gui/GUIHelpers.kt

@@ -0,0 +1,96 @@
+@file:JvmName("GUIHelperExtensions")
+
+package com.willfp.eco.core.gui
+
+import com.willfp.eco.core.gui.menu.Menu
+import com.willfp.eco.core.gui.menu.MenuBuilder
+import com.willfp.eco.core.gui.slot.Slot
+import com.willfp.eco.core.gui.slot.SlotBuilder
+import org.bukkit.entity.Player
+import org.bukkit.event.inventory.InventoryClickEvent
+import org.bukkit.event.inventory.InventoryCloseEvent
+import org.bukkit.inventory.ItemStack
+
+/**
+ * @see SlotBuilder.onLeftClick
+ */
+fun SlotBuilder.onLeftClick(action: (InventoryClickEvent, Slot, Menu) -> Unit): SlotBuilder =
+    this.onLeftClick { a, b, c -> action(a, b, c) }
+
+/**
+ * @see SlotBuilder.onRightClick
+ */
+fun SlotBuilder.onRightClick(action: (InventoryClickEvent, Slot, Menu) -> Unit): SlotBuilder =
+    this.onRightClick { a, b, c -> action(a, b, c) }
+
+/**
+ * @see SlotBuilder.onShiftLeftClick
+ */
+fun SlotBuilder.onShiftLeftClick(action: (InventoryClickEvent, Slot, Menu) -> Unit): SlotBuilder =
+    this.onShiftLeftClick { a, b, c -> action(a, b, c) }
+
+/**
+ * @see SlotBuilder.onShiftRightClick
+ */
+fun SlotBuilder.onShiftRightClick(action: (InventoryClickEvent, Slot, Menu) -> Unit): SlotBuilder =
+    this.onShiftRightClick { a, b, c -> action(a, b, c) }
+
+/**
+ * @see SlotBuilder.onShiftRightClick
+ */
+fun SlotBuilder.onMiddleClick(action: (InventoryClickEvent, Slot, Menu) -> Unit): SlotBuilder =
+    this.onMiddleClick { a, b, c -> action(a, b, c) }
+
+/**
+ * @see SlotBuilder.setModifier
+ */
+fun SlotBuilder.setModifier(action: (Player, Menu, ItemStack) -> Unit): SlotBuilder =
+    this.setModifier { a, b, c -> action(a, b, c) }
+
+/**
+ * Kotlin builder for slots.
+ */
+fun slot(
+    item: ItemStack,
+    init: SlotBuilder.() -> Unit
+): Slot {
+    val builder = Slot.builder(item)
+    init(builder)
+    return builder.build()
+}
+
+/**
+ * Kotlin builder for slots.
+ */
+fun slot(
+    provider: (Player, Menu) -> ItemStack,
+    init: SlotBuilder.() -> Unit
+): Slot {
+    val builder = Slot.builder { a, b -> provider(a, b) }
+    init(builder)
+    return builder.build()
+}
+
+/**
+ * @see MenuBuilder.onClose
+ */
+fun MenuBuilder.onClose(action: (InventoryCloseEvent, Menu) -> Unit): MenuBuilder =
+    this.onClose { a, b -> action(a, b) }
+
+/**
+ * @see MenuBuilder.modify
+ */
+fun MenuBuilder.modify(modifier: (MenuBuilder) -> Unit): MenuBuilder =
+    this.modfiy { modifier(it) }
+
+/**
+ * Kotlin builder for menus.
+ */
+fun menu(
+    rows: Int,
+    init: MenuBuilder.() -> Unit
+): Menu {
+    val builder = Menu.builder(rows)
+    init(builder)
+    return builder.build()
+}

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

@@ -0,0 +1,12 @@
+@file:JvmName("ArrowUtilsExtensions")
+
+package com.willfp.eco.util
+
+import org.bukkit.entity.Arrow
+import org.bukkit.inventory.ItemStack
+
+/**
+ * @see ArrowUtils.getBow
+ */
+val Arrow.bow: ItemStack?
+    get() = ArrowUtils.getBow(this)

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

@@ -0,0 +1,11 @@
+@file:JvmName("BlockUtilsExtensions")
+
+package com.willfp.eco.util
+
+import org.bukkit.block.Block
+
+/**
+ * @see ArrowUtils.getBow
+ */
+val Block.isPlayerPlaced: Boolean
+    get() = BlockUtils.isPlayerPlaced(this)

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

@@ -0,0 +1,15 @@
+@file:JvmName("ListUtilsExtensions")
+
+package com.willfp.eco.util
+
+/**
+ * @see ListUtils.listToFrequencyMap
+ */
+fun <T> List<T>.toFrequencyMap(): Map<T, Int> =
+    ListUtils.listToFrequencyMap(this)
+
+/**
+ * @see ListUtils.containsIgnoreCase
+ */
+fun Iterable<String>.containsIgnoreCase(element: String): Boolean =
+    ListUtils.containsIgnoreCase(this, element)

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

@@ -0,0 +1,26 @@
+@file:JvmName("PlayerUtilsExtensions")
+
+package com.willfp.eco.util
+
+import net.kyori.adventure.audience.Audience
+import org.bukkit.OfflinePlayer
+import org.bukkit.command.CommandSender
+import org.bukkit.entity.Player
+
+/**
+ * @see PlayerUtils.getSavedDisplayName
+ */
+val OfflinePlayer.savedDisplayName: String
+    get() = PlayerUtils.getSavedDisplayName(this)
+
+/**
+ * @see PlayerUtils.getAudience
+ */
+fun Player.asAudience(): Audience =
+    PlayerUtils.getAudience(this)
+
+/**
+ * @see PlayerUtils.getAudience
+ */
+fun CommandSender.asAudience(): Audience =
+    PlayerUtils.getAudience(this)

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

@@ -0,0 +1,11 @@
+@file:JvmName("PotionUtilsExtensions")
+
+package com.willfp.eco.util
+
+import org.bukkit.potion.PotionData
+
+/**
+ * @see PotionData.duration
+ */
+val PotionData.duration: Int
+    get() = PotionUtils.getDuration(this)

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

@@ -0,0 +1,11 @@
+@file:JvmName("ServerUtilsExtensions")
+
+package com.willfp.eco.util
+
+import org.bukkit.Server
+
+/**
+ * @see ServerUtils.getTps
+ */
+val Server.tps: Double
+    get() = ServerUtils.getTps()

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

@@ -0,0 +1,17 @@
+@file:JvmName("SkullUtilsExtensions")
+
+package com.willfp.eco.util
+
+import org.bukkit.inventory.meta.SkullMeta
+
+/**
+ * @see SkullUtils.getSkullTexture
+ * @see SkullUtils.setSkullTexture
+ */
+var SkullMeta.texture: String?
+    get() = SkullUtils.getSkullTexture(this)
+    set(value) {
+        if (value != null) {
+            SkullUtils.setSkullTexture(this, value)
+        }
+    }

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

@@ -0,0 +1,42 @@
+@file:JvmName("StringUtilsExtensions")
+
+package com.willfp.eco.util
+
+import net.kyori.adventure.text.Component
+import org.bukkit.entity.Player
+
+/**
+ * @see StringUtils.toComponent
+ */
+fun String.toComponent(): Component =
+    StringUtils.toComponent(this)
+
+/**
+ * @see StringUtils.toLegacy
+ */
+fun Component.toLegacy(): String =
+    StringUtils.toLegacy(this)
+
+/**
+ * @see StringUtils.format
+ */
+fun String.formatEco(
+    player: Player? = null,
+    formatPlaceholders: Boolean = false
+) = StringUtils.format(
+    this,
+    player,
+    if (formatPlaceholders) StringUtils.FormatOption.WITH_PLACEHOLDERS else StringUtils.FormatOption.WITHOUT_PLACEHOLDERS
+)
+
+/**
+ * @see StringUtils.formatList
+ */
+fun List<String>.formatEco(
+    player: Player? = null,
+    formatPlaceholders: Boolean = false
+) = StringUtils.formatList(
+    this,
+    player,
+    if (formatPlaceholders) StringUtils.FormatOption.WITH_PLACEHOLDERS else StringUtils.FormatOption.WITHOUT_PLACEHOLDERS
+)

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

@@ -0,0 +1,17 @@
+@file:JvmName("VectorUtilsExtensions")
+
+package com.willfp.eco.util
+
+import org.bukkit.util.Vector
+
+/**
+ * @see VectorUtils.isFinite
+ */
+val Vector.isFinite: Boolean
+    get() = VectorUtils.isFinite(this)
+
+/**
+ * @see VectorUtils.simplifyVector
+ */
+fun Vector.simplify(): Vector =
+    VectorUtils.simplifyVector(this)

eco-core/core-backend/build.gradle

@@ -7,5 +7,5 @@ dependencies {
     compileOnly 'org.reflections:reflections:0.9.12'
     compileOnly 'net.kyori:adventure-text-minimessage:4.1.0-SNAPSHOT'
     compileOnly 'net.kyori:adventure-platform-bukkit:4.0.0'
-    compileOnly 'com.google.guava:guava:31.0.1-jre'
+    compileOnly 'org.objenesis:objenesis:3.2'
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/json/EcoJSONConfigWrapper.kt

@@ -7,7 +7,6 @@ import com.google.gson.GsonBuilder
 import com.willfp.eco.core.config.ConfigType
 import com.willfp.eco.core.config.interfaces.JSONConfig
 import com.willfp.eco.util.StringUtils
-import org.bukkit.configuration.file.YamlConfiguration
 import java.util.Objects
 import java.util.concurrent.ConcurrentHashMap
 
@@ -131,24 +130,18 @@ open class EcoJSONConfigWrapper : JSONConfig {
     }
 
     override fun getSubsection(path: String): JSONConfig {
-        val subsection = getSubsectionOrNull(path)
-        return subsection ?: EcoJSONConfigSection(emptyMap())
+        return getSubsectionOrNull(path) ?: EcoJSONConfigSection(mutableMapOf())
     }
 
     override fun getSubsectionOrNull(path: String): JSONConfig? {
         return if (values.containsKey(path)) {
-            val subsection = values[path] as Map<String, Any>?
-            EcoJSONConfigSection(subsection!!)
+            val subsection = values[path] as Map<String, Any>
+            EcoJSONConfigSection(subsection)
         } else {
             null
         }
     }
 
-    override fun getSubsections(path: String): List<JSONConfig> {
-        val subsections = getSubsectionsOrNull(path)
-        return subsections ?: mutableListOf()
-    }
-
     override fun getSubsectionsOrNull(path: String): List<JSONConfig>? {
         val maps = getOfKnownType(path, Any::class.java) as List<Map<String, Any>>?
             ?: return null
@@ -159,74 +152,20 @@ open class EcoJSONConfigWrapper : JSONConfig {
         return configs.toMutableList()
     }
 
-    override fun getInt(path: String): Int {
-        return (getOfKnownType(path, Double::class.java) ?: 0.0).toInt()
-    }
-
     override fun getIntOrNull(path: String): Int? {
-        return if (has(path)) {
-            getInt(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getInt(
-        path: String,
-        def: Int
-    ): Int {
-        return Objects.requireNonNullElse(getOfKnownType(path, Int::class.java), def)
-    }
-
-    override fun getInts(path: String): MutableList<Int> {
-        return (Objects.requireNonNullElse(
-            getOfKnownType(path, Any::class.java),
-            emptyList<Int>()
-        ) as List<Int>).toMutableList()
+        return getOfKnownType(path, Double::class.java)?.toInt()
     }
 
     override fun getIntsOrNull(path: String): MutableList<Int>? {
-        return if (has(path)) {
-            getInts(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getBool(path: String): Boolean {
-        return Objects.requireNonNullElse(getOfKnownType(path, Boolean::class.java), false)
+        return (getOfKnownType(path, Any::class.java) as Collection<Int>?)?.toMutableList()
     }
 
     override fun getBoolOrNull(path: String): Boolean? {
-        return if (has(path)) {
-            getBool(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getBools(path: String): MutableList<Boolean> {
-        return (Objects.requireNonNullElse(
-            getOfKnownType(path, Any::class.java),
-            emptyList<Boolean>()
-        ) as List<Boolean>).toMutableList()
+        return getOfKnownType(path, Boolean::class.java)
     }
 
     override fun getBoolsOrNull(path: String): MutableList<Boolean>? {
-        return if (has(path)) {
-            getBools(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getString(
-        path: String,
-        format: Boolean,
-        option: StringUtils.FormatOption
-    ): String {
-        val string = getOfKnownType(path, String::class.java) ?: ""
-        return if (format) StringUtils.format(string, option) else string
+        return (getOfKnownType(path, Any::class.java) as Collection<Boolean>?)?.toMutableList()
     }
 
     override fun getStringOrNull(
@@ -235,62 +174,36 @@ open class EcoJSONConfigWrapper : JSONConfig {
         option: StringUtils.FormatOption
     ): String? {
         return if (has(path)) {
-            getString(path, format, option)
+            val string = getOfKnownType(path, String::class.java) ?: ""
+            return if (format) StringUtils.format(string, option) else string
         } else {
             null
         }
     }
 
-    override fun getStrings(
-        path: String,
-        format: Boolean,
-        option: StringUtils.FormatOption
-    ): MutableList<String> {
-        val strings =
-            (Objects.requireNonNullElse(
-                getOfKnownType(path, Any::class.java),
-                emptyList<String>()
-            ) as List<String>).toMutableList()
-        return if (format) StringUtils.formatList(strings, option) else strings
-    }
-
     override fun getStringsOrNull(
         path: String,
         format: Boolean,
         option: StringUtils.FormatOption
     ): MutableList<String>? {
         return if (has(path)) {
-            getStrings(path, format, option)
+            val strings =
+                (Objects.requireNonNullElse(
+                    getOfKnownType(path, Any::class.java),
+                    emptyList<String>()
+                ) as List<String>).toMutableList()
+            return if (format) StringUtils.formatList(strings, option) else strings
         } else {
             null
         }
     }
 
-    override fun getDouble(path: String): Double {
-        return Objects.requireNonNullElse(getOfKnownType(path, Double::class.java), 0.0)
-    }
-
     override fun getDoubleOrNull(path: String): Double? {
-        return if (has(path)) {
-            getDouble(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getDoubles(path: String): MutableList<Double> {
-        return (Objects.requireNonNullElse(
-            getOfKnownType(path, Any::class.java),
-            emptyList<Double>()
-        ) as List<Double>).toMutableList()
+        return getOfKnownType(path, Double::class.java)
     }
 
     override fun getDoublesOrNull(path: String): MutableList<Double>? {
-        return if (has(path)) {
-            getDoubles(path)
-        } else {
-            null
-        }
+        return (getOfKnownType(path, Any::class.java) as Collection<Double>?)?.toMutableList()
     }
 
     override fun getType(): ConfigType {

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/json/EcoLoadableJSONConfig.kt

@@ -24,11 +24,7 @@ open class EcoLoadableJSONConfig(
     private val name: String = "$configName.json"
 
     fun reloadFromFile() {
-        try {
-            init(configFile)
-        } catch (e: IOException) {
-            e.printStackTrace()
-        }
+        runCatching { init(configFile) }.onFailure { it.printStackTrace() }
     }
 
     final override fun createFile() {
@@ -94,11 +90,7 @@ open class EcoLoadableJSONConfig(
             createFile()
         }
         configFile = File(directory, name)
-        try {
-            init(configFile)
-        } catch (e: IOException) {
-            e.printStackTrace()
-        }
+        init(configFile)
         plugin.configHandler.addConfig(this)
     }
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/json/EcoUpdatableJSONConfig.kt

@@ -1,10 +1,8 @@
 package com.willfp.eco.internal.config.json
 
 import com.willfp.eco.core.PluginLike
-import org.bukkit.configuration.InvalidConfigurationException
 import org.bukkit.configuration.file.YamlConfiguration
 import java.io.BufferedReader
-import java.io.IOException
 import java.io.InputStreamReader
 import java.nio.charset.StandardCharsets
 
@@ -21,48 +19,36 @@ open class EcoUpdatableJSONConfig(
 
     fun update() {
         super.clearCache()
-        try {
-            this.init(configFile)
-            val newConfig = configInJar
-            if (newConfig.getKeys(true) == this.getKeys(true)) {
-                return
-            }
-            newConfig.getKeys(true).forEach { key: String ->
-                if (!this.getKeys(true).contains(key)) {
-                    if (updateBlacklist.stream().noneMatch { s: String -> key.contains(s) }) {
-                        this.set(key, newConfig[key])
-                    }
-                }
-            }
-            if (removeUnused) {
-                this.getKeys(true).forEach { s ->
-                    if (!newConfig.getKeys(true).contains(s)) {
-                        if (updateBlacklist.stream().noneMatch(s::contains)) {
-                            this.set(s, null)
-                        }
-                    }
-                }
-            }
-            this.save()
-        } catch (e: IOException) {
-            e.printStackTrace()
-        } catch (e: InvalidConfigurationException) {
-            e.printStackTrace()
+        this.init(configFile)
+        val newConfig = configInJar ?: return
+        if (newConfig.getKeys(true) == this.getKeys(true)) {
+            return
         }
+        newConfig.getKeys(true).forEach { key: String ->
+            if (!this.getKeys(true).contains(key)) {
+                if (updateBlacklist.stream().noneMatch { s: String -> key.contains(s) }) {
+                    this.set(key, newConfig[key])
+                }
+            }
+        }
+        if (removeUnused) {
+            this.getKeys(true).forEach { s ->
+                if (!newConfig.getKeys(true).contains(s)) {
+                    if (updateBlacklist.stream().noneMatch(s::contains)) {
+                        this.set(s, null)
+                    }
+                }
+            }
+        }
+        this.save()
     }
 
-    private val configInJar: YamlConfiguration
+    private val configInJar: YamlConfiguration?
         get() {
-            val newIn = this.source.getResourceAsStream(resourcePath) ?: throw NullPointerException("$name is null?")
+            val newIn = this.source.getResourceAsStream(resourcePath) ?: return null
             val reader = BufferedReader(InputStreamReader(newIn, StandardCharsets.UTF_8))
             val newConfig = YamlConfiguration()
-            try {
-                newConfig.load(reader)
-            } catch (e: IOException) {
-                e.printStackTrace()
-            } catch (e: InvalidConfigurationException) {
-                e.printStackTrace()
-            }
+            newConfig.load(reader)
             return newConfig
         }
 

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/updating/EcoConfigHandler.kt

@@ -24,15 +24,15 @@ class EcoConfigHandler(
 
     override fun callUpdate() {
         for (method in reflections.getMethodsAnnotatedWith(ConfigUpdater::class.java)) {
-            try {
+            kotlin.runCatching {
                 when (method.parameterCount) {
                     0 -> method.invoke(null)
                     1 -> method.invoke(null, this.plugin)
                     else -> throw InvalidUpdateMethodException("Update method must have 0 parameters or a plugin parameter.")
                 }
-            } catch (e: ReflectiveOperationException) {
-                e.printStackTrace()
-                throw InvalidUpdateMethodException("Update method generated an exception")
+            }.onFailure {
+                it.printStackTrace()
+                plugin.logger.severe("Update method ${method.toGenericString()} generated an exception")
             }
         }
     }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/yaml/EcoLoadableYamlConfig.kt

@@ -5,7 +5,6 @@ package com.willfp.eco.internal.config.yaml
 import com.willfp.eco.core.PluginLike
 import com.willfp.eco.core.config.interfaces.LoadableConfig
 import com.willfp.eco.core.config.interfaces.WrappedYamlConfiguration
-import org.bukkit.configuration.InvalidConfigurationException
 import org.bukkit.configuration.file.YamlConfiguration
 import java.io.File
 import java.io.FileOutputStream
@@ -23,13 +22,7 @@ open class EcoLoadableYamlConfig(
     private val name: String = "$configName.yml"
 
     fun reloadFromFile() {
-        try {
-            handle.load(getConfigFile())
-        } catch (e: IOException) {
-            e.printStackTrace()
-        } catch (e: InvalidConfigurationException) {
-            e.printStackTrace()
-        }
+        handle.load(getConfigFile())
     }
 
     final override fun createFile() {

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/yaml/EcoUpdatableYamlConfig.kt

@@ -1,10 +1,8 @@
 package com.willfp.eco.internal.config.yaml
 
 import com.willfp.eco.core.PluginLike
-import org.bukkit.configuration.InvalidConfigurationException
 import org.bukkit.configuration.file.YamlConfiguration
 import java.io.BufferedReader
-import java.io.IOException
 import java.io.InputStreamReader
 import java.nio.charset.StandardCharsets
 
@@ -21,48 +19,36 @@ class EcoUpdatableYamlConfig(
 
     fun update() {
         super.clearCache()
-        try {
-            this.handle.load(configFile)
-            val newConfig = configInJar
-            if (newConfig.getKeys(true) == this.handle.getKeys(true)) {
-                return
-            }
-            newConfig.getKeys(true).forEach { key ->
-                if (!this.handle.getKeys(true).contains(key)) {
-                    if (updateBlacklist.stream().noneMatch { key.contains(it) }) {
-                        this.handle.set(key, newConfig[key])
-                    }
-                }
-            }
-            if (removeUnused) {
-                this.handle.getKeys(true).forEach { s ->
-                    if (!newConfig.getKeys(true).contains(s)) {
-                        if (updateBlacklist.stream().noneMatch(s::contains)) {
-                            this.handle.set(s, null)
-                        }
-                    }
-                }
-            }
-            this.handle.save(configFile)
-        } catch (e: IOException) {
-            e.printStackTrace()
-        } catch (e: InvalidConfigurationException) {
-            e.printStackTrace()
+        this.handle.load(configFile)
+        val newConfig = configInJar ?: return
+        if (newConfig.getKeys(true) == this.handle.getKeys(true)) {
+            return
         }
+        newConfig.getKeys(true).forEach { key ->
+            if (!this.handle.getKeys(true).contains(key)) {
+                if (updateBlacklist.stream().noneMatch { key.contains(it) }) {
+                    this.handle.set(key, newConfig[key])
+                }
+            }
+        }
+        if (removeUnused) {
+            this.handle.getKeys(true).forEach { s ->
+                if (!newConfig.getKeys(true).contains(s)) {
+                    if (updateBlacklist.stream().noneMatch(s::contains)) {
+                        this.handle.set(s, null)
+                    }
+                }
+            }
+        }
+        this.handle.save(configFile)
     }
 
-    private val configInJar: YamlConfiguration
+    private val configInJar: YamlConfiguration?
         get() {
-            val newIn = source.getResourceAsStream(resourcePath) ?: throw NullPointerException("$name is null?")
+            val newIn = source.getResourceAsStream(resourcePath) ?: return null
             val reader = BufferedReader(InputStreamReader(newIn, StandardCharsets.UTF_8))
             val newConfig = YamlConfiguration()
-            try {
-                newConfig.load(reader)
-            } catch (e: IOException) {
-                e.printStackTrace()
-            } catch (e: InvalidConfigurationException) {
-                e.printStackTrace()
-            }
+            newConfig.load(reader)
             return newConfig
         }
 

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/yaml/EcoYamlConfigWrapper.kt

@@ -49,11 +49,6 @@ open class EcoYamlConfigWrapper<T : ConfigurationSection> : Config {
         handle[path] = obj
     }
 
-    override fun getSubsection(path: String): Config {
-        val subsection = getSubsectionOrNull(path)
-        return subsection ?: EcoYamlConfigSection(YamlConfiguration())
-    }
-
     override fun getSubsectionOrNull(path: String): Config? {
         return if (cache.containsKey(path)) {
             cache[path] as Config?
@@ -68,109 +63,55 @@ open class EcoYamlConfigWrapper<T : ConfigurationSection> : Config {
         }
     }
 
-    override fun getInt(path: String): Int {
-        return if (cache.containsKey(path)) {
-            (cache[path] as Number).toInt()
-        } else {
-            cache[path] = handle.getDouble(path, 0.0).toInt()
-            getInt(path)
-        }
-    }
-
     override fun getIntOrNull(path: String): Int? {
-        return if (has(path)) {
-            getInt(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getInt(
-        path: String,
-        def: Int
-    ): Int {
         return if (cache.containsKey(path)) {
             (cache[path] as Number).toInt()
         } else {
-            cache[path] = handle.getDouble(path, def.toDouble()).toInt()
-            getInt(path)
-        }
-    }
-
-    override fun getInts(path: String): MutableList<Int> {
-        return if (cache.containsKey(path)) {
-            (cache[path] as MutableList<Int>).toMutableList()
-        } else {
-            cache[path] = if (has(path)) ArrayList(handle.getIntegerList(path)) else mutableListOf<Int>()
-            getInts(path)
+            if (has(path)) {
+                cache[path] = handle.getDouble(path).toInt()
+            } else {
+                return null
+            }
+            getIntOrNull(path)
         }
     }
 
     override fun getIntsOrNull(path: String): MutableList<Int>? {
-        return if (has(path)) {
-            getInts(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getBool(path: String): Boolean {
         return if (cache.containsKey(path)) {
-            cache[path] as Boolean
+            (cache[path] as Collection<Int>).toMutableList()
         } else {
-            cache[path] = handle.getBoolean(path)
-            getBool(path)
+            if (has(path)) {
+                cache[path] = handle.getIntegerList(path).toMutableList()
+            } else {
+                return null
+            }
+            getIntsOrNull(path)
         }
     }
 
     override fun getBoolOrNull(path: String): Boolean? {
-        return if (has(path)) {
-            getBool(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getBools(path: String): MutableList<Boolean> {
         return if (cache.containsKey(path)) {
-            (cache[path] as MutableList<Boolean>).toMutableList()
+            cache[path] as Boolean
         } else {
-            cache[path] =
-                if (has(path)) ArrayList(handle.getBooleanList(path)) else mutableListOf<Boolean>()
-            getBools(path)
+            if (has(path)) {
+                cache[path] = handle.getBoolean(path)
+            } else {
+                return null
+            }
+            getBoolOrNull(path)
         }
     }
 
     override fun getBoolsOrNull(path: String): MutableList<Boolean>? {
-        return if (has(path)) {
-            getBools(path)
+        return if (cache.containsKey(path)) {
+            (cache[path] as Collection<Boolean>).toMutableList()
         } else {
-            null
-        }
-    }
-
-    override fun getString(
-        path: String,
-        format: Boolean,
-        option: StringUtils.FormatOption
-    ): String {
-        if (format && option == StringUtils.FormatOption.WITHOUT_PLACEHOLDERS) {
-            return if (cache.containsKey("$path\$FMT")) {
-                cache["$path\$FMT"] as String
+            if (has(path)) {
+                cache[path] = handle.getBooleanList(path).toMutableList()
             } else {
-                val string: String = handle.getString(path, "")!!
-                cache["$path\$FMT"] = StringUtils.format(string, option)
-                getString(path, format, option)
+                return null
             }
-        } else {
-            val string = if (cache.containsKey(path)) {
-                cache[path] as String
-            } else {
-                cache[path] = handle.getString(path, "")!!
-                getString(path, format, option)
-            }
-
-            return if (format) StringUtils.format(string) else string
+            getBoolsOrNull(path)
         }
     }
 
@@ -180,108 +121,105 @@ open class EcoYamlConfigWrapper<T : ConfigurationSection> : Config {
         option: StringUtils.FormatOption
     ): String? {
         return if (has(path)) {
-            getString(path, format, option)
+            if (format && option == StringUtils.FormatOption.WITHOUT_PLACEHOLDERS) {
+                return if (cache.containsKey("$path\$FMT")) {
+                    cache["$path\$FMT"] as String
+                } else {
+                    val string: String = handle.getString(path, "")!!
+                    cache["$path\$FMT"] = StringUtils.format(string, option)
+                    getString(path, format, option)
+                }
+            } else {
+                val string = if (cache.containsKey(path)) {
+                    cache[path] as String
+                } else {
+                    cache[path] = handle.getString(path, "")!!
+                    getString(path, format, option)
+                }
+
+                return if (format) StringUtils.format(string) else string
+            }
         } else {
             null
         }
     }
 
-    override fun getStrings(
-        path: String,
-        format: Boolean,
-        option: StringUtils.FormatOption
-    ): MutableList<String> {
-        if (format && option == StringUtils.FormatOption.WITHOUT_PLACEHOLDERS) {
-            return if (cache.containsKey("$path\$FMT")) {
-                (cache["$path\$FMT"] as MutableList<String>).toMutableList()
-            } else {
-                val list = if (has(path)) handle.getStringList(path) else mutableListOf<String>()
-                cache["$path\$FMT"] = StringUtils.formatList(list, option)
-                getStrings(path, true, option)
-            }
-        } else {
-            val strings = if (cache.containsKey(path)) {
-                (cache[path] as MutableList<String>).toMutableList()
-            } else {
-                cache[path] =
-                    if (has(path)) ArrayList(handle.getStringList(path)) else mutableListOf<String>()
-                getStrings(path, false, option)
-            }
-
-            return if (format) {
-                StringUtils.formatList(strings, StringUtils.FormatOption.WITH_PLACEHOLDERS)
-            } else {
-                strings
-            }
-        }
-    }
-
     override fun getStringsOrNull(
         path: String,
         format: Boolean,
         option: StringUtils.FormatOption
     ): MutableList<String>? {
         return if (has(path)) {
-            getStrings(path, format, option)
+            if (format && option == StringUtils.FormatOption.WITHOUT_PLACEHOLDERS) {
+                return if (cache.containsKey("$path\$FMT")) {
+                    (cache["$path\$FMT"] as MutableList<String>).toMutableList()
+                } else {
+                    val list = if (has(path)) handle.getStringList(path) else mutableListOf<String>()
+                    cache["$path\$FMT"] = StringUtils.formatList(list, option)
+                    getStrings(path, true, option)
+                }
+            } else {
+                val strings = if (cache.containsKey(path)) {
+                    (cache[path] as MutableList<String>).toMutableList()
+                } else {
+                    cache[path] =
+                        if (has(path)) ArrayList(handle.getStringList(path)) else mutableListOf<String>()
+                    getStrings(path, false, option)
+                }
+
+                return if (format) {
+                    StringUtils.formatList(strings, StringUtils.FormatOption.WITH_PLACEHOLDERS)
+                } else {
+                    strings
+                }
+            }
         } else {
             null
         }
     }
 
-    override fun getDouble(path: String): Double {
-        return if (cache.containsKey(path)) {
-            cache[path] as Double
-        } else {
-            cache[path] = handle.getDouble(path)
-            getDouble(path)
-        }
-    }
-
     override fun getDoubleOrNull(path: String): Double? {
-        return if (has(path)) {
-            getDouble(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getDoubles(path: String): MutableList<Double> {
         return if (cache.containsKey(path)) {
-            (cache[path] as MutableList<Double>).toMutableList()
+            (cache[path] as Number).toDouble()
         } else {
-            cache[path] = if (has(path)) ArrayList(handle.getDoubleList(path)) else emptyList<Double>()
-            getDoubles(path)
+            if (has(path)) {
+                cache[path] = handle.getDouble(path)
+            } else {
+                return null
+            }
+            getDoubleOrNull(path)
         }
     }
 
     override fun getDoublesOrNull(path: String): MutableList<Double>? {
-        return if (has(path)) {
-            getDoubles(path)
-        } else {
-            null
-        }
-    }
-
-    override fun getSubsections(path: String): MutableList<out Config> {
         return if (cache.containsKey(path)) {
-            (cache[path] as Collection<Config>).toMutableList()
+            (cache[path] as Collection<Double>).toMutableList()
         } else {
-            val mapList = ArrayList(handle.getMapList(path)) as List<Map<String, Any?>>
-            val configList = mutableListOf<Config>()
-            for (map in mapList) {
-                val temp = YamlConfiguration.loadConfiguration(StringReader(""))
-                temp.createSection("a", map)
-                configList.add(EcoYamlConfigSection(temp.getConfigurationSection("a")!!))
+            if (has(path)) {
+                cache[path] = handle.getDoubleList(path).toMutableList()
+            } else {
+                return null
             }
-
-            cache[path] = if (has(path)) configList else emptyList()
-            getSubsections(path)
+            getDoublesOrNull(path)
         }
     }
 
     override fun getSubsectionsOrNull(path: String): MutableList<out Config>? {
         return if (has(path)) {
-            getSubsections(path)
+            return if (cache.containsKey(path)) {
+                (cache[path] as Collection<Config>).toMutableList()
+            } else {
+                val mapList = ArrayList(handle.getMapList(path)) as List<Map<String, Any?>>
+                val configList = mutableListOf<Config>()
+                for (map in mapList) {
+                    val temp = YamlConfiguration.loadConfiguration(StringReader(""))
+                    temp.createSection("a", map)
+                    configList.add(EcoYamlConfigSection(temp.getConfigurationSection("a")!!))
+                }
+
+                cache[path] = if (has(path)) configList else emptyList()
+                getSubsections(path)
+            }
         } else {
             null
         }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/drops/impl/EcoDropQueue.kt

@@ -73,12 +73,10 @@ open class EcoDropQueue(val player: Player) : InternalDropQueue {
                 world.dropItem(location, drop!!).velocity = Vector()
             }
             if (xp > 0) {
-                val event = PlayerExpChangeEvent(player, xp)
-                Bukkit.getPluginManager().callEvent(event)
                 val orb =
                     world.spawnEntity(player.location.add(0.0, 0.2, 0.0), EntityType.EXPERIENCE_ORB) as ExperienceOrb
                 orb.velocity = Vector(0, 0, 0)
-                orb.experience = event.amount
+                orb.experience = xp
             }
         } else {
             for (drop in items) {
@@ -94,4 +92,4 @@ open class EcoDropQueue(val player: Player) : InternalDropQueue {
     init {
         location = player.location
     }
-}
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserAdult.kt

@@ -0,0 +1,34 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.entity.Animals
+
+class EntityArgParserAdult : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var baby = false
+
+        for (arg in args) {
+            if (arg.equals("adult", true)) {
+                baby = true
+            }
+        }
+
+        if (!baby) {
+            return null
+        }
+
+        return EntityArgParseResult(
+            {
+                if (it !is Animals) {
+                    return@EntityArgParseResult false
+                }
+
+                it.isAdult
+            },
+            {
+                (it as? Animals)?.setAdult()
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserAttackDamage.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserAttackDamage : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("attack-damage", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.GENERIC_ATTACK_DAMAGE) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_ATTACK_DAMAGE)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserAttackSpeed.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserAttackSpeed : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("attack-speed", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.GENERIC_ATTACK_SPEED) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_ATTACK_SPEED)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserBaby.kt

@@ -0,0 +1,34 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.entity.Animals
+
+class EntityArgParserBaby : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var baby = false
+
+        for (arg in args) {
+            if (arg.equals("baby", true)) {
+                baby = true
+            }
+        }
+
+        if (!baby) {
+            return null
+        }
+
+        return EntityArgParseResult(
+            {
+                if (it !is Animals) {
+                    return@EntityArgParseResult false
+                }
+
+                !it.isAdult
+            },
+            {
+                (it as? Animals)?.setBaby()
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserCharged.kt

@@ -0,0 +1,34 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.entity.Creeper
+
+class EntityArgParserCharged : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var noAI = false
+
+        for (arg in args) {
+            if (arg.equals("charged", true)) {
+                noAI = true
+            }
+        }
+
+        if (!noAI) {
+            return null
+        }
+
+        return EntityArgParseResult(
+            {
+                if (it !is Creeper) {
+                    return@EntityArgParseResult false
+                }
+
+                it.isPowered
+            },
+            {
+                (it as? Creeper)?.isPowered = true
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserExplosionRadius.kt

@@ -0,0 +1,38 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.entity.Creeper
+
+class EntityArgParserExplosionRadius : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var size: Int? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("explosion-radius", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            size = argSplit[1].toIntOrNull()
+        }
+
+        size ?: return null
+
+        return EntityArgParseResult(
+            {
+                when (it) {
+                    is Creeper -> it.explosionRadius == size
+                    else -> false
+                }
+            },
+            {
+                when (it) {
+                    is Creeper -> it.explosionRadius = size
+                }
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserFlySpeed.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserFlySpeed : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("fly-speed", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.GENERIC_FLYING_SPEED) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_FLYING_SPEED)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserFollowRange.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserFollowRange : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("follow-range", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.GENERIC_FOLLOW_RANGE) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_FOLLOW_RANGE)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserHealth.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserHealth : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var health: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("health", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            health = argSplit[1].toDoubleOrNull()
+        }
+
+        health ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                it.health >= health
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_MAX_HEALTH)?.baseValue = health
+                it.health = health
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserJumpStrength.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserJumpStrength : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("jump-strength", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.HORSE_JUMP_STRENGTH) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.HORSE_JUMP_STRENGTH)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserKnockback.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserKnockback : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("knockback", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.GENERIC_ATTACK_KNOCKBACK) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_ATTACK_KNOCKBACK)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserKnockbackResistance.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserKnockbackResistance : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("knockback-resistance", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.GENERIC_KNOCKBACK_RESISTANCE) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_KNOCKBACK_RESISTANCE)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserName.kt

@@ -0,0 +1,34 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import com.willfp.eco.util.StringUtils
+
+class EntityArgParserName : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var name: String? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("name", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            name = argSplit[1]
+        }
+
+        name ?: return null
+
+        val formatted = StringUtils.format(name)
+
+        return EntityArgParseResult(
+            { it.customName == formatted },
+            {
+                it.isCustomNameVisible = true
+                it.customName = formatted
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserNoAI.kt

@@ -0,0 +1,34 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserNoAI : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var noAI = false
+
+        for (arg in args) {
+            if (arg.equals("no-ai", true)) {
+                noAI = true
+            }
+        }
+
+        if (!noAI) {
+            return null
+        }
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                !it.hasAI()
+            },
+            {
+                (it as? LivingEntity)?.setAI(false)
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserSilent.kt

@@ -0,0 +1,30 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.entity.Animals
+
+class EntityArgParserSilent : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var silent = false
+
+        for (arg in args) {
+            if (arg.equals("silent", true)) {
+                silent = true
+            }
+        }
+
+        if (!silent) {
+            return null
+        }
+
+        return EntityArgParseResult(
+            {
+                it.isSilent
+            },
+            {
+                it.isSilent = true
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserSize.kt

@@ -0,0 +1,41 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.entity.Phantom
+import org.bukkit.entity.Slime
+
+class EntityArgParserSize : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var size: Int? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("size", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            size = argSplit[1].toIntOrNull()
+        }
+
+        size ?: return null
+
+        return EntityArgParseResult(
+            {
+                when (it) {
+                    is Slime -> it.size == size
+                    is Phantom -> it.size == size
+                    else -> false
+                }
+            },
+            {
+                when (it) {
+                    is Slime -> it.size = size
+                    is Phantom -> it.size = size
+                }
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserSpawnReinforcements.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserSpawnReinforcements : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("spawn-reinforcements", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.ZOMBIE_SPAWN_REINFORCEMENTS) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.ZOMBIE_SPAWN_REINFORCEMENTS)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserSpeed.kt

@@ -0,0 +1,43 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+
+class EntityArgParserSpeed : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("speed", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.GENERIC_MOVEMENT_SPEED) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_MOVEMENT_SPEED)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/extensions/EcoExtensionLoader.kt

@@ -1,6 +1,7 @@
 package com.willfp.eco.internal.extensions
 
 import com.google.common.collect.ImmutableSet
+import com.willfp.eco.core.Eco
 import com.willfp.eco.core.EcoPlugin
 import com.willfp.eco.core.config.TransientConfig
 import com.willfp.eco.core.extensions.Extension
@@ -10,8 +11,6 @@ import com.willfp.eco.core.extensions.MalformedExtensionException
 import org.bukkit.configuration.file.YamlConfiguration
 import java.io.File
 import java.io.InputStreamReader
-import java.net.MalformedURLException
-import java.net.URL
 import java.net.URLClassLoader
 
 class EcoExtensionLoader(
@@ -32,23 +31,18 @@ class EcoExtensionLoader(
                 continue
             }
 
-            try {
-                loadExtension(extensionJar)
-            } catch (e: MalformedExtensionException) {
+            runCatching { loadExtension(extensionJar) }.onFailure {
                 this.plugin.logger.warning(extensionJar.name + " caused an error!")
+                if (Eco.getHandler().ecoPlugin.configYml.getBool("log-full-extension-errors")) {
+                    it.printStackTrace()
+                }
             }
         }
     }
 
     @Throws(MalformedExtensionException::class)
     private fun loadExtension(extensionJar: File) {
-        lateinit var url: URL
-
-        try {
-            url = extensionJar.toURI().toURL()
-        } catch (e: MalformedURLException) {
-            e.printStackTrace()
-        }
+        val url = extensionJar.toURI().toURL()
 
         val classLoader = URLClassLoader(arrayOf(url), this.plugin::class.java.classLoader)
         val ymlIn = classLoader.getResourceAsStream("extension.yml")

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/factory/EcoNamespacedKeyFactory.kt

@@ -2,10 +2,11 @@ package com.willfp.eco.internal.factory
 
 import com.willfp.eco.core.EcoPlugin
 import com.willfp.eco.core.factory.NamespacedKeyFactory
+import com.willfp.eco.util.NamespacedKeyUtils
 import org.bukkit.NamespacedKey
 
 class EcoNamespacedKeyFactory(private val plugin: EcoPlugin) : NamespacedKeyFactory {
     override fun create(key: String): NamespacedKey {
-        return NamespacedKey(plugin, key)
+        return NamespacedKeyUtils.create(plugin.name, key)
     }
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/fast/InternalNamespacedKeyFactory.kt

@@ -0,0 +1,31 @@
+package com.willfp.eco.internal.fast
+
+import org.bukkit.NamespacedKey
+import org.objenesis.ObjenesisStd
+
+interface InternalNamespacedKeyFactory {
+    fun create(namespace: String, key: String): NamespacedKey
+}
+
+class FastInternalNamespacedKeyFactory : InternalNamespacedKeyFactory {
+    private val creator = ObjenesisStd().getInstantiatorOf(NamespacedKey::class.java)
+    private val namespaceField = NamespacedKey::class.java.getDeclaredField("namespace")
+        .apply { isAccessible = true }
+    private val keyField = NamespacedKey::class.java.getDeclaredField("key")
+        .apply { isAccessible = true }
+
+
+    override fun create(namespace: String, key: String): NamespacedKey {
+        val namespacedKey = creator.newInstance()
+        keyField.set(namespacedKey, key.lowercase())
+        namespaceField.set(namespacedKey, namespace.lowercase())
+        return namespacedKey
+    }
+}
+
+class SafeInternalNamespacedKeyFactory : InternalNamespacedKeyFactory {
+    override fun create(namespace: String, key: String): NamespacedKey {
+        @Suppress("DEPRECATION")
+        return NamespacedKey(namespace, key)
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/gui/slot/EcoSlotBuilder.kt

@@ -8,7 +8,7 @@ import com.willfp.eco.core.gui.slot.functional.SlotProvider
 
 class EcoSlotBuilder(private val provider: SlotProvider) : SlotBuilder {
     private var captive = false
-    private var modifier: SlotModifier = SlotModifier{ player, menu, _ -> provider.provide(player, menu)}
+    private var modifier: SlotModifier = SlotModifier { player, menu, _ -> provider.provide(player, menu) }
 
     private var onLeftClick =
         SlotHandler { _, _, _ -> run { } }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/integrations/PlaceholderIntegrationPAPI.kt

@@ -32,7 +32,7 @@ class PlaceholderIntegrationPAPI(private val plugin: EcoPlugin) : PlaceholderExp
         player: Player?,
         identifier: String
     ): String {
-        return PlaceholderManager.getResult(player, identifier)
+        return PlaceholderManager.getResult(player, identifier, plugin)
     }
 
     override fun registerIntegration() {
@@ -49,4 +49,14 @@ class PlaceholderIntegrationPAPI(private val plugin: EcoPlugin) : PlaceholderExp
     ): String {
         return PlaceholderAPI.setPlaceholders(player, text)
     }
+
+    override fun findPlaceholdersIn(text: String): MutableList<String> {
+        val placeholders = mutableListOf<String>()
+        val matcher = PlaceholderAPI.getPlaceholderPattern().matcher(text)
+        while (matcher.find()) {
+            placeholders.add(matcher.group())
+        }
+
+        return placeholders
+    }
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/items/ArgParserEnchantment.kt

@@ -2,7 +2,7 @@ package com.willfp.eco.internal.items
 
 import com.willfp.eco.core.fast.FastItemStack
 import com.willfp.eco.core.items.args.LookupArgParser
-import org.bukkit.NamespacedKey
+import com.willfp.eco.util.NamespacedKeyUtils
 import org.bukkit.enchantments.Enchantment
 import org.bukkit.inventory.ItemStack
 import org.bukkit.inventory.meta.EnchantmentStorageMeta
@@ -20,7 +20,7 @@ class ArgParserEnchantment : LookupArgParser {
                 continue
             }
 
-            val enchant = Enchantment.getByKey(NamespacedKey.minecraft(argSplit[0].lowercase()))
+            val enchant = Enchantment.getByKey(NamespacedKeyUtils.create("minecraft", argSplit[0]))
             val level = argSplit[1].toIntOrNull()
 
             if (enchant != null && level != null) {

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/items/ArgParserFlag.kt

@@ -11,12 +11,7 @@ class ArgParserFlag : LookupArgParser {
         val flags = mutableSetOf<ItemFlag>()
 
         for (arg in args) {
-            val flag = try {
-                ItemFlag.valueOf(arg.uppercase())
-            } catch (e: Exception) {
-                null
-            } ?: continue
-
+            val flag = kotlin.runCatching { ItemFlag.valueOf(arg.uppercase()) }.getOrNull() ?: continue
             flags.add(flag)
         }
 

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/items/ArgParserName.kt

@@ -18,7 +18,7 @@ class ArgParserName : LookupArgParser {
             if (argSplit.size < 2) {
                 continue
             }
-            name = argSplit[1].replace("_", "")
+            name = argSplit[1]
         }
 
         name ?: return null

eco-core/core-nms/v1_16_R3/src/main/kotlin/com/willfp/eco/internal/spigot/proxy/v1_16_R3/DummyEntity.kt

@@ -0,0 +1,15 @@
+package com.willfp.eco.internal.spigot.proxy.v1_16_R3
+
+import com.willfp.eco.internal.spigot.proxy.DummyEntityProxy
+import org.bukkit.Location
+import org.bukkit.craftbukkit.v1_16_R3.CraftWorld
+import org.bukkit.entity.Entity
+import org.bukkit.entity.EntityType
+
+class DummyEntity : DummyEntityProxy {
+    override fun createDummyEntity(location: Location): Entity {
+        val world = location.world as CraftWorld
+        @Suppress("UsePropertyAccessSyntax")
+        return world.createEntity(location, EntityType.ZOMBIE.entityClass).getBukkitEntity()
+    }
+}