diff --git a/eco-core/core-plugin/src/main/java/com/willfp/ecobosses/bosses/listeners/AttackListeners.java b/eco-core/core-plugin/src/main/java/com/willfp/ecobosses/bosses/listeners/AttackListeners.java
index 1787799..8d7be29 100644
--- a/eco-core/core-plugin/src/main/java/com/willfp/ecobosses/bosses/listeners/AttackListeners.java
+++ b/eco-core/core-plugin/src/main/java/com/willfp/ecobosses/bosses/listeners/AttackListeners.java
@@ -148,6 +148,10 @@ public class AttackListeners extends PluginDependent implements Listener {
 
         LivingEcoBoss livingEcoBoss = boss.getLivingBoss(entity);
 
+        if (livingEcoBoss == null) {
+            return;
+        }
+
         livingEcoBoss.handleAttack(player);
     }
 
diff --git a/eco-core/core-plugin/src/main/java/com/willfp/ecobosses/bosses/listeners/AutoSpawnTimer.java b/eco-core/core-plugin/src/main/java/com/willfp/ecobosses/bosses/listeners/AutoSpawnTimer.java
index e72b75a..8470c7d 100644
--- a/eco-core/core-plugin/src/main/java/com/willfp/ecobosses/bosses/listeners/AutoSpawnTimer.java
+++ b/eco-core/core-plugin/src/main/java/com/willfp/ecobosses/bosses/listeners/AutoSpawnTimer.java
@@ -8,6 +8,7 @@ import com.willfp.ecobosses.bosses.LivingEcoBoss;
 import org.bukkit.Bukkit;
 import org.bukkit.Location;
 import org.bukkit.World;
+import org.bukkit.entity.Entity;
 
 import java.util.ArrayList;
 import java.util.HashSet;
@@ -34,7 +35,14 @@ public class AutoSpawnTimer implements Runnable {
             Set<World> worlds = new HashSet<>();
 
             for (UUID uuid : boss.getLivingBosses().keySet()) {
-                worlds.add(Bukkit.getEntity(uuid).getWorld());
+                Entity entity = Bukkit.getEntity(uuid);
+
+                if (entity == null) {
+                    boss.removeLivingBoss(uuid);
+                    continue;
+                }
+
+                worlds.add(entity.getWorld());
             }
 
             List<Location> locations = new ArrayList<>(boss.getAutoSpawnLocations());