"Messenger of Death" is an episode of The Itchy & Scratchy Show.
There's a knock at Scratchy's door. Scratchy answers the door to find Itchy standing on his front porch, wearing a messenger's uniform and carrying a bazooka. Itchy fires the bazooka, hitting Scratchy in the head and blowing the flesh away, leaving only a charred skull sitting on top of his neck. As the smoke clears, the skull falls off.