Debut: Proteus/Kevin MacTaggert.
Cameo: Technet, a group of bounty hunters (Body Bag, Thug, Ferro Squared, Waxworks, Gate Crasher, Ring Toss).
Morph appears in a cameo role, connected to some diagnostic equipment in the establishing shots of the Muir Island Facility. He does not participate in the story, nor does he interact with any of his fellow X-Men.
Amelia Voght appears as the nurse during the montage of Professor Xavier's memories. She also appears as one of Magneto's Acolytes in Sanctuary Part I (1995) and Sanctuary Part II (1995).