His war has been won. The few humans left alive are enslaved; the mutant rebellion crushed. En Sabah Nur, Apocalypse, rules his Battleworld kingdom without mercy — but the terrorist X-Men plan to end his reign! For Magneto and his X-Men, success means finding a very special mutant named Cypher and unleashing a weapon that will kill Apocalypse — and possibly all other mutants, as well! As the X-Men face Cyclops and Havok's Elite Mutant Force, Angel finds himself protecting a "flatscan" named Jean Grey, and Dr. Nemesis must sabotage Dark Beast's quest to become the newest Horseman of Apocalypse! As the race to claim the Legacy virus grows desperate, the X-Men, the Horseman and the human insurgency clash! The devastating plague begins claiming mutants' lives — but if Apocalypse falls, who will rule in his place?