Always one with a bad attitude, Jason Stryker was dangerous and made his parents fear him. For this reason, his father, William Stryker, sent Jason to the Xavier's School for Gifted Youngsters. However, Charles Xavier was unable to help Jason and sent him back to William. After Jason got his mother killed, he was lobotomized by his father and used in his sadistic experiments. Eventually Jason was used to try and get Charles to nearly kill all mutants, and then Magneto for all humans. However, when the dam at Alkali Lake burst, Jason was left to die by Kurt Wagner.
Jason could trap all beings, even telepaths, in an illusion world. Through this, he could manipulate the beings trapped in his illusions. Jason's spinal cord also produced a fluid used to take over the minds of people.