diff --git a/plugin/src/main/java/net/momirealms/customfishing/CustomFishingPluginImpl.java b/plugin/src/main/java/net/momirealms/customfishing/CustomFishingPluginImpl.java
index cc5cf9be..f5338e95 100644
--- a/plugin/src/main/java/net/momirealms/customfishing/CustomFishingPluginImpl.java
+++ b/plugin/src/main/java/net/momirealms/customfishing/CustomFishingPluginImpl.java
@@ -55,6 +55,7 @@ import net.momirealms.customfishing.version.VersionManagerImpl;
 import org.bstats.bukkit.Metrics;
 import org.bukkit.Bukkit;
 import org.bukkit.configuration.file.YamlConfiguration;
+import org.bukkit.entity.Player;
 import org.bukkit.event.HandlerList;
 import org.jetbrains.annotations.NotNull;
 
@@ -120,29 +121,29 @@ public class CustomFishingPluginImpl extends CustomFishingPlugin {
 
     @Override
     public void onDisable() {
-        ((AdventureManagerImpl) this.adventure).close();
-        ((BagManagerImpl) this.bagManager).disable();
-        ((BlockManagerImpl) this.blockManager).disable();
-        ((EffectManagerImpl) this.effectManager).disable();
-        ((FishingManagerImpl) this.fishingManager).disable();
-        ((GameManagerImpl) this.gameManager).disable();
-        ((ItemManagerImpl) this.itemManager).disable();
-        ((LootManagerImpl) this.lootManager).disable();
-        ((MarketManagerImpl) this.marketManager).disable();
-        ((EntityManagerImpl) this.entityManager).disable();
-        ((RequirementManagerImpl) this.requirementManager).disable();
-        ((SchedulerImpl) this.scheduler).shutdown();
-        ((IntegrationManagerImpl) this.integrationManager).disable();
-        ((CompetitionManagerImpl) this.competitionManager).disable();
-        ((StorageManagerImpl) this.storageManager).disable();
-        ((PlaceholderManagerImpl) this.placeholderManager).disable();
-        ((StatisticsManagerImpl) this.statisticsManager).disable();
-        ((ActionManagerImpl) this.actionManager).disable();
-        ((TotemManagerImpl) this.totemManager).disable();
-        ((HookManagerImpl) this.hookManager).disable();
-        this.coolDownManager.disable();
-        this.chatCatcherManager.disable();
-        this.commandManager.unload();
+        if (this.adventure != null) ((AdventureManagerImpl) this.adventure).close();
+        if (this.bagManager != null) ((BagManagerImpl) this.bagManager).disable();
+        if (this.blockManager != null) ((BlockManagerImpl) this.blockManager).disable();
+        if (this.effectManager != null) ((EffectManagerImpl) this.effectManager).disable();
+        if (this.fishingManager != null) ((FishingManagerImpl) this.fishingManager).disable();
+        if (this.gameManager != null) ((GameManagerImpl) this.gameManager).disable();
+        if (this.itemManager != null) ((ItemManagerImpl) this.itemManager).disable();
+        if (this.lootManager != null) ((LootManagerImpl) this.lootManager).disable();
+        if (this.marketManager != null) ((MarketManagerImpl) this.marketManager).disable();
+        if (this.entityManager != null) ((EntityManagerImpl) this.entityManager).disable();
+        if (this.requirementManager != null) ((RequirementManagerImpl) this.requirementManager).disable();
+        if (this.scheduler != null) ((SchedulerImpl) this.scheduler).shutdown();
+        if (this.integrationManager != null) ((IntegrationManagerImpl) this.integrationManager).disable();
+        if (this.competitionManager != null) ((CompetitionManagerImpl) this.competitionManager).disable();
+        if (this.storageManager != null) ((StorageManagerImpl) this.storageManager).disable();
+        if (this.placeholderManager != null) ((PlaceholderManagerImpl) this.placeholderManager).disable();
+        if (this.statisticsManager != null) ((StatisticsManagerImpl) this.statisticsManager).disable();
+        if (this.actionManager != null) ((ActionManagerImpl) this.actionManager).disable();
+        if (this.totemManager != null) ((TotemManagerImpl) this.totemManager).disable();
+        if (this.hookManager != null) ((HookManagerImpl) this.hookManager).disable();
+        if (this.coolDownManager != null) this.coolDownManager.disable();
+        if (this.chatCatcherManager != null) this.chatCatcherManager.disable();
+        if (this.commandManager != null) this.commandManager.unload();
         HandlerList.unregisterAll(this);
     }
 
diff --git a/plugin/src/main/java/net/momirealms/customfishing/mechanic/competition/Competition.java b/plugin/src/main/java/net/momirealms/customfishing/mechanic/competition/Competition.java
index 1da461b1..cd4da07d 100644
--- a/plugin/src/main/java/net/momirealms/customfishing/mechanic/competition/Competition.java
+++ b/plugin/src/main/java/net/momirealms/customfishing/mechanic/competition/Competition.java
@@ -93,7 +93,7 @@ public class Competition implements FishingCompetition {
 
         Action[] actions = config.getStartActions();
         if (actions != null) {
-            Condition condition = new Condition(null, null, new HashMap<>());
+            Condition condition = new Condition(null, null, this.publicPlaceholders);
             for (Action action : actions) {
                 action.trigger(condition);
             }
@@ -186,14 +186,14 @@ public class Competition implements FishingCompetition {
                     Player player = Bukkit.getPlayer(competitionPlayer.left());
                     if (player != null)
                         for (Action action : rewardsMap.get(String.valueOf(i)))
-                            action.trigger(new Condition(player));
+                            action.trigger(new Condition(player, this.publicPlaceholders));
                 } else {
                     Action[] actions = rewardsMap.get("participation");
                     if (actions != null) {
                         Player player = Bukkit.getPlayer(competitionPlayer.left()); {
                             if (player != null)
                                 for (Action action : actions)
-                                    action.trigger(new Condition(player));
+                                    action.trigger(new Condition(player, this.publicPlaceholders));
                         }
                     }
                 }
diff --git a/plugin/src/main/java/net/momirealms/customfishing/mechanic/requirement/RequirementManagerImpl.java b/plugin/src/main/java/net/momirealms/customfishing/mechanic/requirement/RequirementManagerImpl.java
index cc19fb60..480dd131 100644
--- a/plugin/src/main/java/net/momirealms/customfishing/mechanic/requirement/RequirementManagerImpl.java
+++ b/plugin/src/main/java/net/momirealms/customfishing/mechanic/requirement/RequirementManagerImpl.java
@@ -44,6 +44,8 @@ import org.bukkit.configuration.MemorySection;
 import org.bukkit.configuration.file.YamlConfiguration;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
+import org.bukkit.potion.PotionEffect;
+import org.bukkit.potion.PotionEffectType;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -199,6 +201,7 @@ public class RequirementManagerImpl implements RequirementManager {
         this.registerCompetitionRequirement();
         this.registerListRequirement();
         this.registerEnvironmentRequirement();
+        this.registerPotionEffectRequirement();
     }
 
     public HashMap<String, Double> getLootWithWeight(Condition condition) {
@@ -1139,11 +1142,59 @@ public class RequirementManagerImpl implements RequirementManager {
                 };
             } else {
                 LogUtils.warn("Wrong value format found at plugin-level requirement.");
-                return null;
+                return EmptyRequirement.instance;
             }
         });
     }
 
+
+    private void registerPotionEffectRequirement() {
+        registerRequirement("potion-effect", (args, actions, advanced) -> {
+            String potions = (String) args;
+            String[] split = potions.split("(<=|>=|<|>|==)", 2);
+            PotionEffectType type = PotionEffectType.getByName(split[0]);
+            if (type == null) {
+                LogUtils.warn("Potion effect doesn't exist: " + split[0]);
+                return EmptyRequirement.instance;
+            }
+            int required = Integer.parseInt(split[1]);
+            String operator = potions.substring(split[0].length(), potions.length() - split[1].length());
+            return condition -> {
+                int level = -1;
+                PotionEffect potionEffect = condition.getPlayer().getPotionEffect(type);
+                if (potionEffect != null) {
+                    level = potionEffect.getAmplifier();
+                }
+                boolean result = false;
+                switch (operator) {
+                    case ">=" -> {
+                        if (level >= required) result = true;
+                    }
+                    case ">" -> {
+                        if (level > required) result = true;
+                    }
+                    case "==" -> {
+                        if (level == required) result = true;
+                    }
+                    case "!=" -> {
+                        if (level != required) result = true;
+                    }
+                    case "<=" -> {
+                        if (level <= required) result = true;
+                    }
+                    case "<" -> {
+                        if (level < required) result = true;
+                    }
+                }
+                if (result) {
+                    return true;
+                }
+                if (advanced) triggerActions(actions, condition);
+                return false;
+            };
+        });
+    }
+
     /**
      * Triggers a list of actions with the given condition.
      * If the list of actions is not null, each action in the list is triggered.