Age of Apocalypse
Rex acted as Apocalypse's personal assistant, carrying out orders and running errands. He was intimately involved in the torture of Karma and the shutting down of the Breeding Pens.
It is not known if Rex is a mutant or a human. It is unlikely that Apocalypse kept a human in his employ, though Rex has been referred to as both "flatscan" and "mutate". In any event, he did not exhibit any mutant powers.
He uses Blink
´s teleport trayectory to find the x-men
headquarters in Xavier´s Mansion