Armagheadon

 is a non-playable character in MultiVersus.

Origin
Armagheadon is the leader of the Cromulons and host of the intergalactic TV reality show "Planet Music" who made his debut in the fifth episode of the second season of Rick and Morty, "Get Schwifty". He was also worshiped as a god by the now defunct religious cult known as Headism.

Role in MultiVersus
Armagheadon can be seen in the background of the Cromulons Map, observing the Fighters during combat.

Trivia

 * Armagheadon has a lot of unused voice lines left in the game files, all reused from his debut episode from Rick and Morty, which were probably intended for use on the Cromulons Map. It is unknown whether or not they will be added in a future update.
 * One of said voice lines is heard at the end of Rick's Gameplay Trailer.

External

 * Armagheadon on Rick and Morty Wiki.