The body count rises higher than ever as the X-Men and their allies face war on every front! The original X-Men have formed X-Factor, and they come up against their deadliest challenge yet in Apocalypse and his Horsemen, including the all-new Archangel! The New Mutants lose one of their own! And after the Marauders slaughter the Morlocks, they take on the X-Men - and the survivors will be asked to sacrifice themselves to stop the evil Adversary! Featuring tie-ins starring Captain America, Daredevil, the Hulk, the Fantastic Four and Power Pack! Collecting NEW MUTANTS (1983) #55-61, UNCANNY X-MEN #220-227, X-FACTOR (1986) #18-26, CAPTAIN AMERICA (1968) #339, DAREDEVIL (1964) #252, FANTASTIC FOUR (1961) #312, INCREDIBLE HULK (1968) #336-337 & #340 and POWER PACK (1984) #35.