diff --git a/pom.xml b/pom.xml
index 3ab1981..1f1065b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -65,7 +65,7 @@
         <!-- Do not change unless you want different name for local builds. -->
         <build.number>-LOCAL</build.number>
         <!-- This allows to change between versions. -->
-        <build.version>1.15.1</build.version>
+        <build.version>1.15.2</build.version>
         <!-- Sonar Cloud -->
         <sonar.projectKey>BentoBoxWorld_AcidIsland</sonar.projectKey>
         <sonar.organization>bentobox-world</sonar.organization>
diff --git a/src/main/java/world/bentobox/acidisland/world/AcidTask.java b/src/main/java/world/bentobox/acidisland/world/AcidTask.java
index e190e08..1e9dab2 100644
--- a/src/main/java/world/bentobox/acidisland/world/AcidTask.java
+++ b/src/main/java/world/bentobox/acidisland/world/AcidTask.java
@@ -1,7 +1,7 @@
 package world.bentobox.acidisland.world;
 
 import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -21,6 +21,8 @@
 import org.bukkit.entity.WaterMob;
 import org.bukkit.scheduler.BukkitTask;
 
+import com.google.common.base.Enums;
+
 import world.bentobox.acidisland.AcidIsland;
 import world.bentobox.acidisland.events.EntityDamageByAcidEvent;
 import world.bentobox.acidisland.events.EntityDamageByAcidEvent.Acid;
@@ -29,7 +31,15 @@
 
 public class AcidTask {
     private final AcidIsland addon;
-    private static final List<EntityType> IMMUNE = Arrays.asList(EntityType.TURTLE, EntityType.POLAR_BEAR, EntityType.DROWNED, EntityType.AXOLOTL);
+    private static final List<EntityType> IMMUNE;
+    static {
+        List<EntityType> i = new ArrayList<>();
+        i.add(EntityType.POLAR_BEAR);
+        i.add(EntityType.TURTLE);
+        i.add(EntityType.DROWNED);
+        Enums.getIfPresent(EntityType.class, "AXOLOTL").toJavaUtil().ifPresent(i::add);
+        IMMUNE = Collections.unmodifiableList(i);
+    }
     private Map<Entity, Long> itemsInWater = new ConcurrentHashMap<>();
     private final BukkitTask findMobsTask;
 
diff --git a/src/main/resources/addon.yml b/src/main/resources/addon.yml
index f31684a..e519db3 100755
--- a/src/main/resources/addon.yml
+++ b/src/main/resources/addon.yml
@@ -1,7 +1,7 @@
 name: AcidIsland
 main: world.bentobox.acidisland.AcidIsland
 version: ${version}${build.number}
-api-version: ${bentobox.version}
+api-version: 1.16.5
 metrics: true
 repository: "BentoBoxWorld/AcidIsland"
 icon: "OAK_BOAT"