Xorn

In the fictional Marvel Universe, while on a mission to Asia, Cyclops and Emma Frost found a mutant healer named Xorn, who returned with them to the mansion. He was a valued member of the team, even going so far as to heal Professor Xavier's legs.

Soon he was put in charge of the "special" class, who he soon commanded as an unofficial team of X-Men. However, this proved to work against them when he took off his helmet to reveal none other than the X-Men's arch-foe Magneto, and he once again crippled Xavier.