PaperMC/nms-patches/PathfinderGoalHurtByTarget.patch

--- a/net/minecraft/server/PathfinderGoalHurtByTarget.java
+++ b/net/minecraft/server/PathfinderGoalHurtByTarget.java
@@ -49,7 +49,7 @@
 
     @Override
     public void c() {
-        this.e.setGoalTarget(this.e.getLastDamager());
+        this.e.setGoalTarget(this.e.getLastDamager(), org.bukkit.event.entity.EntityTargetEvent.TargetReason.TARGET_ATTACKED_ENTITY, true); // CraftBukkit - reason
         this.g = this.e.getGoalTarget();
         this.c = this.e.cs();
         this.h = 300;
@@ -95,6 +95,6 @@
     }
 
     protected void a(EntityInsentient entityinsentient, EntityLiving entityliving) {
-        entityinsentient.setGoalTarget(entityliving);
+        entityinsentient.setGoalTarget(entityliving, org.bukkit.event.entity.EntityTargetEvent.TargetReason.TARGET_ATTACKED_NEARBY_ENTITY, true); // CraftBukkit - reason
     }
 }