Fabian Cortez

Fabian Cortez was Magneto's second in command of the Acolytes.

History
Cortez used his powers to bolster Magneto’s own abilities. However, Cortez’s extreme anti-human sentiments led him to betray Magneto and try to kill him, framing Professor X, Beast and Gambit, capturing and torturing the latter. Cortez threatened to destroy Earth but was stopped by the X-Men and Amelia Voght, who revealed Cortez’s betrayal to the other Acolytes and the entire mutant population of Asteroid M. He was trapped in Asteroid M by a vengeful Magneto, but was rescued from its destruction by Apocalypse and Deathbird.

Apocalypse granted Cortez the ability of altering the mutations of other mutants, so he turned into a servant and worshipper of his savior. Cortez assembled a cult worshipping Apocalypse as well as the Hounds, a foursome of altered mutants, in an attempt to find a new body for Apocalypse (who was defeated and left bodyless in “Beyond Good and Evil”). Cortez captured Jubilee and turned Beast into a feral monster but was stopped by Caliban. After being defeated, Cortez begged Apocalypse to be forgiven for his failure. However, Apocalypse was not angry and simply took possession of Cortez's body.