The Pacodemon is the love child of a Cacodemon and Pain elemental. It can shoot electrical energy balls shaped like skulls that steer their way towards the player, but explode upon impact. Much like the Nitro-Golem's fire attack from Heretic.
It was supposed to be part a before and after picture. An image of a pain elemental holding hands with a Cacodemon being the before part, but I then realized the caco has no arms so I just made the end result.