diff --git a/pom.xml b/pom.xml
index f308891d..e9730ddf 100644
--- a/pom.xml
+++ b/pom.xml
@@ -125,7 +125,7 @@
 		<dependency>
 			<groupId>io.lumine</groupId>
 			<artifactId>MythicLib</artifactId>
-			<version>1.1.3</version>
+			<version>1.1.4</version>
 			<scope>provided</scope>
 		</dependency>
 
diff --git a/src/main/java/net/Indyuce/mmocore/api/player/PlayerData.java b/src/main/java/net/Indyuce/mmocore/api/player/PlayerData.java
index 927dedf1..94f17fad 100644
--- a/src/main/java/net/Indyuce/mmocore/api/player/PlayerData.java
+++ b/src/main/java/net/Indyuce/mmocore/api/player/PlayerData.java
@@ -1,8 +1,8 @@
 package net.Indyuce.mmocore.api.player;
 
-import io.lumine.mythic.lib.api.player.MMOPlayerData;
-import io.lumine.mythic.lib.player.CooldownInfo;
-import io.lumine.mythic.lib.player.CooldownMap;
+import io.lumine.mythic.lib.player.MMOPlayerData;
+import io.lumine.mythic.lib.player.cooldown.CooldownInfo;
+import io.lumine.mythic.lib.player.cooldown.CooldownMap;
 import net.Indyuce.mmocore.MMOCore;
 import net.Indyuce.mmocore.api.ConfigMessage;
 import net.Indyuce.mmocore.api.Waypoint;
@@ -19,6 +19,7 @@ import net.Indyuce.mmocore.api.player.social.guilds.Guild;
 import net.Indyuce.mmocore.api.player.stats.PlayerStats;
 import net.Indyuce.mmocore.api.player.stats.StatType;
 import net.Indyuce.mmocore.api.quest.PlayerQuests;
+import net.Indyuce.mmocore.api.util.Closable;
 import net.Indyuce.mmocore.api.util.MMOCoreUtils;
 import net.Indyuce.mmocore.api.util.math.particle.SmallParticleEffect;
 import net.Indyuce.mmocore.experience.EXPSource;
@@ -45,7 +46,7 @@ import java.util.*;
 import java.util.logging.Level;
 
 
-public class PlayerData extends OfflinePlayerData {
+public class PlayerData extends OfflinePlayerData implements Closable {
 
     /**
      * Corresponds to the MythicLib player data. It is used to keep
@@ -127,6 +128,11 @@ public class PlayerData extends OfflinePlayerData {
             }
     }
 
+    @Override
+    public void close() {
+        questData.close();
+    }
+
     public MMOPlayerData getMMOPlayerData() {
         return mmoData;
     }
@@ -896,7 +902,23 @@ public class PlayerData extends OfflinePlayerData {
      * @return If player data for that player is loaded
      */
     public static boolean has(Player player) {
-        return MMOCore.plugin.dataProvider.getDataManager().isLoaded(player.getUniqueId());
+       return has(player.getUniqueId());
+    }
+
+    /**
+     * This is used to check if the player data is loaded for a
+     * specific player. This might seem redundant because the given
+     * Player instance is linked to an online player, and data
+     * is always loaded for an online player.
+     * <p>
+     * In fact a Player instance can be attached to a Citizens NPC
+     * which has no player data loaded hence this method
+     *
+     * @param uuid A (real or fictive) player UUID
+     * @return If player data for that player is loaded
+     */
+    public static boolean has(UUID uuid) {
+        return MMOCore.plugin.dataProvider.getDataManager().isLoaded(uuid);
     }
 
     public static Collection<PlayerData> getAll() {
diff --git a/src/main/java/net/Indyuce/mmocore/api/quest/ObjectiveProgress.java b/src/main/java/net/Indyuce/mmocore/api/quest/ObjectiveProgress.java
index cb747478..92e56216 100644
--- a/src/main/java/net/Indyuce/mmocore/api/quest/ObjectiveProgress.java
+++ b/src/main/java/net/Indyuce/mmocore/api/quest/ObjectiveProgress.java
@@ -1,5 +1,6 @@
 package net.Indyuce.mmocore.api.quest;
 
+import net.Indyuce.mmocore.api.util.Closable;
 import org.bukkit.Bukkit;
 import org.bukkit.event.HandlerList;
 import org.bukkit.event.Listener;
@@ -8,7 +9,7 @@ import net.Indyuce.mmocore.MMOCore;
 import net.Indyuce.mmocore.api.player.PlayerData;
 import net.Indyuce.mmocore.api.quest.objective.Objective;
 
-public abstract class ObjectiveProgress {
+public abstract class ObjectiveProgress implements Closable {
 	private final Objective objective;
 	private final QuestProgress questProgress;
 
@@ -32,6 +33,7 @@ public abstract class ObjectiveProgress {
 		return questProgress;
 	}
 
+	@Override
 	public void close() {
 		if (this instanceof Listener)
 			HandlerList.unregisterAll((Listener) this);
diff --git a/src/main/java/net/Indyuce/mmocore/api/quest/PlayerQuests.java b/src/main/java/net/Indyuce/mmocore/api/quest/PlayerQuests.java
index dbb3a980..37b66d9d 100644
--- a/src/main/java/net/Indyuce/mmocore/api/quest/PlayerQuests.java
+++ b/src/main/java/net/Indyuce/mmocore/api/quest/PlayerQuests.java
@@ -6,6 +6,7 @@ import com.google.gson.JsonObject;
 import io.lumine.mythic.lib.MythicLib;
 import net.Indyuce.mmocore.MMOCore;
 import net.Indyuce.mmocore.api.player.PlayerData;
+import net.Indyuce.mmocore.api.util.Closable;
 import org.bukkit.NamespacedKey;
 import org.bukkit.boss.BarColor;
 import org.bukkit.boss.BarStyle;
@@ -19,7 +20,7 @@ import java.util.Map.Entry;
 import java.util.Set;
 import java.util.logging.Level;
 
-public class PlayerQuests {
+public class PlayerQuests implements Closable {
     private final PlayerData playerData;
     private final BossBar bossbar;
     private final Map<String, Long> finished = new HashMap<>();
@@ -36,12 +37,6 @@ public class PlayerQuests {
             bossbar.addPlayer(playerData.getPlayer());
     }
 
-    @Deprecated
-    public PlayerQuests(PlayerData playerData, BossBar bar) {
-        this.playerData = playerData;
-        this.bossbar = bar;
-    }
-
     public PlayerQuests load(ConfigurationSection config) {
         if (config.contains("current"))
             try {
@@ -148,15 +143,20 @@ public class PlayerQuests {
 
     public void start(Quest quest) {
 
-        // close current objective progress if quest is active
-        if (hasCurrent())
-            current.getProgress().close();
+        // Close current objective progress if quest is active
+        close();
 
-        // apply newer quest
+        // Apply newest quest
         current = quest == null ? null : quest.generateNewProgress(playerData);
         updateBossBar();
     }
 
+    @Override
+    public void close() {
+        if (current != null)
+            current.getProgress().close();
+    }
+
     public boolean checkCooldownAvailability(Quest quest) {
         return (finished.get(quest.getId()) + quest.getDelayMillis()) < System.currentTimeMillis();
     }
diff --git a/src/main/java/net/Indyuce/mmocore/api/util/Closable.java b/src/main/java/net/Indyuce/mmocore/api/util/Closable.java
new file mode 100644
index 00000000..4b5283f3
--- /dev/null
+++ b/src/main/java/net/Indyuce/mmocore/api/util/Closable.java
@@ -0,0 +1,15 @@
+package net.Indyuce.mmocore.api.util;
+
+/**
+ * Indicates that a class temporarily registers something
+ * such as a Bukkit event, which needs to be unregistered
+ * when the class is finally garbage collected.
+ */
+public interface Closable {
+
+    /**
+     * Method that must be called before the class
+     * is garbage collected
+     */
+    void close();
+}
diff --git a/src/main/java/net/Indyuce/mmocore/manager/data/PlayerDataManager.java b/src/main/java/net/Indyuce/mmocore/manager/data/PlayerDataManager.java
index 27294614..e9a8cc7e 100644
--- a/src/main/java/net/Indyuce/mmocore/manager/data/PlayerDataManager.java
+++ b/src/main/java/net/Indyuce/mmocore/manager/data/PlayerDataManager.java
@@ -34,7 +34,12 @@ public abstract class PlayerDataManager {
         return Objects.requireNonNull(data.get(uuid), "Player data is not loaded");
     }
 
-    public void remove(UUID uuid) {
+    /**
+     * Clears the data map from a certain key
+     *
+     * @param uuid Player UUID to clear
+     */
+    protected void unregisterData(UUID uuid) {
         data.remove(uuid);
     }
 
diff --git a/src/main/java/net/Indyuce/mmocore/manager/data/mysql/MySQLPlayerDataManager.java b/src/main/java/net/Indyuce/mmocore/manager/data/mysql/MySQLPlayerDataManager.java
index 9383b1e4..ddde0b4a 100644
--- a/src/main/java/net/Indyuce/mmocore/manager/data/mysql/MySQLPlayerDataManager.java
+++ b/src/main/java/net/Indyuce/mmocore/manager/data/mysql/MySQLPlayerDataManager.java
@@ -238,7 +238,10 @@ public class MySQLPlayerDataManager extends PlayerDataManager {
 
 	@Override
 	public void remove(PlayerData data) {
-		if (data.isFullyLoaded()) saveData(data);
-		remove(data.getUniqueId());
+		if (data.isFullyLoaded())
+			saveData(data);
+
+		data.close();
+		unregisterData(data.getUniqueId());
 	}
 }
diff --git a/src/main/java/net/Indyuce/mmocore/manager/data/yaml/YAMLPlayerDataManager.java b/src/main/java/net/Indyuce/mmocore/manager/data/yaml/YAMLPlayerDataManager.java
index cc0e4f4b..baf7b9ad 100644
--- a/src/main/java/net/Indyuce/mmocore/manager/data/yaml/YAMLPlayerDataManager.java
+++ b/src/main/java/net/Indyuce/mmocore/manager/data/yaml/YAMLPlayerDataManager.java
@@ -129,5 +129,8 @@ public class YAMLPlayerDataManager extends PlayerDataManager {
 	}
 
 	@Override
-	public void remove(PlayerData data) {}
+	public void remove(PlayerData data) {
+		data.close();
+		unregisterData(data.getUniqueId());
+	}
 }