Abstract angel level to a separate interface

src/main/java/org/spongepowered/api/data/Keys.java

@@ -118,6 +118,7 @@
 import org.spongepowered.api.entity.ExperienceOrb;
 import org.spongepowered.api.entity.FallingBlock;
 import org.spongepowered.api.entity.Item;
+import org.spongepowered.api.entity.Neutral;
 import org.spongepowered.api.entity.Ownable;
 import org.spongepowered.api.entity.ai.goal.GoalExecutorTypes;
 import org.spongepowered.api.entity.display.BillboardType;
@@ -372,7 +373,7 @@ public final class Keys {
     public static final Key<Value<SoundType>> AMBIENT_SOUND = Keys.key(ResourceKey.sponge("ambient_sound"), SoundType.class);
 
     /**
-     * The anger level of a {@link ZombifiedPiglin}.
+     * The anger level of a {@link Neutral}.
      *
      * <p>Unlike {@link Keys#IS_ANGRY}, the aggressiveness represented by this key may
      * fade over time and the entity will become peaceful again once its anger

src/main/java/org/spongepowered/api/entity/Neutral.java

@@ -0,0 +1,40 @@
+/*
+ * This file is part of SpongeAPI, licensed under the MIT License (MIT).
+ *
+ * Copyright (c) SpongePowered <https://www.spongepowered.org>
+ * Copyright (c) contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package org.spongepowered.api.entity;
+
+import org.spongepowered.api.data.Keys;
+import org.spongepowered.api.data.value.Value;
+
+public interface Neutral extends Entity {
+
+    /**
+     * {@link Keys#ANGER_LEVEL}
+     *
+     * @return The anger level, decays over time
+     */
+    default Value.Mutable<Integer> angerLevel() {
+        return this.requireValue(Keys.ANGER_LEVEL).asMutable();
+    }
+}

src/main/java/org/spongepowered/api/entity/living/animal/Bee.java

@@ -25,9 +25,10 @@
 package org.spongepowered.api.entity.living.animal;
 
 import org.spongepowered.api.entity.Aerial;
+import org.spongepowered.api.entity.Neutral;
 
 /**
  * Represents a Bee.
  */
-public interface Bee extends Animal, Aerial {
+public interface Bee extends Animal, Aerial, Neutral {
 }

src/main/java/org/spongepowered/api/entity/living/animal/PolarBear.java

@@ -26,11 +26,12 @@
 
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.entity.Neutral;
 
 /**
  * Represents a Polar Bear.
  */
-public interface PolarBear extends Animal {
+public interface PolarBear extends Animal, Neutral {
 
     /**
      * {@link Keys#IS_STANDING}

src/main/java/org/spongepowered/api/entity/living/animal/Wolf.java

@@ -27,11 +27,12 @@
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.type.DyeColor;
 import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.entity.Neutral;
 
 /**
  * Represents a Wolf.
  */
-public interface Wolf extends TameableAnimal {
+public interface Wolf extends TameableAnimal, Neutral {
 
     /**
      * {@link Keys#IS_ANGRY}

src/main/java/org/spongepowered/api/entity/living/golem/IronGolem.java

@@ -26,11 +26,12 @@
 
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.entity.Neutral;
 
 /**
  * Represents an Iron Golem.
  */
-public interface IronGolem extends Golem {
+public interface IronGolem extends Golem, Neutral {
 
     /**
      * {@link Keys#IS_PLAYER_CREATED}

src/main/java/org/spongepowered/api/entity/living/monster/Enderman.java

@@ -26,12 +26,13 @@
 
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.entity.Neutral;
 import org.spongepowered.api.entity.living.Monster;
 
 /**
  * Represents an Enderman.
  */
-public interface Enderman extends Monster {
+public interface Enderman extends Monster, Neutral {
 
     /**
      * {@link Keys#IS_SCREAMING}.

src/main/java/org/spongepowered/api/entity/living/monster/zombie/ZombifiedPiglin.java

@@ -26,20 +26,12 @@
 
 import org.spongepowered.api.data.Keys;
 import org.spongepowered.api.data.value.Value;
+import org.spongepowered.api.entity.Neutral;
 
 /**
  * Represents a Zombie Pigman.
  */
-public interface ZombifiedPiglin extends Zombie {
-
-    /**
-     * {@link Keys#ANGER_LEVEL}
-     *
-     * @return The anger level, decays over time
-     */
-    default Value.Mutable<Integer> angerLevel() {
-        return this.requireValue(Keys.ANGER_LEVEL).asMutable();
-    }
+public interface ZombifiedPiglin extends Zombie, Neutral {
 
     /**
      * {@link Keys#IS_ANGRY}