Collects Uncanny X-Men (1981) #318-321, X-Men (1991) #38-41, X-Men Unlimited (1993) #4-7, X-Men Annual (1992) #3, X-Factor (1986) #107-109, Cable (1993) #20. The epic story that ushered in the Age of Apocalypse! Legion’s once-shattered psyche is finally united, with a singular purpose: to make up for all the misery he has visited on his father, Charles Xavier. And to do it, he plans to make Xavier’s dream a reality — by traveling back in time to kill its greatest obstacle, Magneto! The X-Men scramble to stop him from altering history — but, lost in the past, can they thwart Legion’s misguided mission before the entire Marvel Universe is wiped away? Plus: Mystique seeks revenge against Legion, even as her shocking connection to Nightcrawler is revealed! And Storm returns to Cairo to face her past, but will she join the all-new Hellfire Club?