diff --git a/src/main/java/com/songoda/ultimatestacker/entity/Check.java b/src/main/java/com/songoda/ultimatestacker/entity/Check.java
index fa6e454..a8dd5df 100644
--- a/src/main/java/com/songoda/ultimatestacker/entity/Check.java
+++ b/src/main/java/com/songoda/ultimatestacker/entity/Check.java
@@ -1,5 +1,8 @@
 package com.songoda.ultimatestacker.entity;
 
+import java.util.HashMap;
+import java.util.Map;
+
 public enum Check {
 
     SPAWN_REASON(false),
@@ -35,7 +38,14 @@ public enum Check {
     PHANTOM_SIZE(true),
     CAT_TYPE(true);
 
-    private boolean isEnabledByDefault;
+    private final boolean isEnabledByDefault;
+    private final static Map<String, Check> checks = new HashMap();
+
+    static {
+        for (Check c : values()) {
+            checks.put(c.name(), c);
+        }
+    }
 
     Check(boolean isEnabledByDefault) {
         this.isEnabledByDefault = isEnabledByDefault;
@@ -44,4 +54,8 @@ public enum Check {
     public boolean isEnabledByDefault() {
         return isEnabledByDefault;
     }
+
+    public static Check getCheck(String name) {
+        return name != null ? checks.get(name.toUpperCase()) : null;
+    }
 }
diff --git a/src/main/java/com/songoda/ultimatestacker/utils/EntityUtils.java b/src/main/java/com/songoda/ultimatestacker/utils/EntityUtils.java
index b82de0d..8b3839b 100644
--- a/src/main/java/com/songoda/ultimatestacker/utils/EntityUtils.java
+++ b/src/main/java/com/songoda/ultimatestacker/utils/EntityUtils.java
@@ -17,12 +17,12 @@ public class EntityUtils {
 
     UltimateStacker plugin = UltimateStacker.getInstance();
 
-    private List<String> checks = Settings.STACK_CHECKS.getStringList();
-    private boolean stackFlyingDown = Settings.ONLY_STACK_FLYING_DOWN.getBoolean();
-    private boolean keepFire = Settings.KEEP_FIRE.getBoolean();
-    private boolean keepPotion = Settings.KEEP_POTION.getBoolean();
-    private boolean stackWholeChunk = Settings.STACK_WHOLE_CHUNK.getBoolean();
-    private int searchRadius = Settings.SEARCH_RADIUS.getInt();
+    private final List<String> checks = Settings.STACK_CHECKS.getStringList();
+    private final boolean stackFlyingDown = Settings.ONLY_STACK_FLYING_DOWN.getBoolean();
+    private final boolean keepFire = Settings.KEEP_FIRE.getBoolean();
+    private final boolean keepPotion = Settings.KEEP_POTION.getBoolean();
+    private final boolean stackWholeChunk = Settings.STACK_WHOLE_CHUNK.getBoolean();
+    private final int searchRadius = Settings.SEARCH_RADIUS.getInt();
 
     private final Map<CachedChunk, Entity[]> cachedChunks = new HashMap<>();
 
@@ -251,7 +251,8 @@ public class EntityUtils {
             entityList.removeIf(entity -> entity.getLocation().getY() > initalEntity.getLocation().getY());
 
         for (String checkStr : checks) {
-            Check check = Check.valueOf(checkStr);
+            Check check = Check.getCheck(checkStr);
+            if (check == null) continue;
             switch (check) {
                 case SPAWN_REASON: {
                     if (initalEntity.hasMetadata("US_REASON"))