His appearance is a thinly veiled disguise of his true form, that which is a giant humanoid cock-roach from the planet Smogula. He wears a respirator that pumps polluted air into his lungs in order for him to survive.
Killemoff uses a number of pollution based devices and weapons in order to take over the world and make it suitable for an invasion from his home world, his primary target being Tromaville. His plans are always foiled by the Toxic Crusaders or the the stupid mishaps of his two mutant henchmen, Bone Head and Psycho. He is second in command to Czar Zoster, the pint sized ruler of Smogula.