Glitched Mobs After Kill

Hey, I'm trying to create a custom mobs plugin, and when I'm killing the mob it glitches out.
Here's how I kill the mob:

Code:

public static void killEntity(Entity entity){
        Creature creature = (Creature) entity;
        CraftCreature craftCreature = (CraftCreature) creature;
        EntityCreature entityCreature = craftCreature.getHandle();
        entityCreature.killEntity();
    }

And it glitches out like that:

The only way I can kill these glitched entities is by removing (entity.remove()) the entity, even the Vanilla /kill command doesn't work. Any help appreciated!

 

@MrBakbuki
Use Creature#setHealth(0)

 

Tried that, still glitched

Anyone?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

If you can use .remove() to get rid of the entity just make a delayed task that removes it after like 5 ticks or so and you will have your animation, You can also add particles to imitate the white particles made when something dies.