Ahhh.. Age of Apocalypse where all X-Titles got suspended for 4 months.
Storyline
Legion (David Haller), an extremely powerful psionic mutant and son of Professor Charles Xavier and Israeli diplomat Gabrielle Haller, travels back in time with the intention of killing Magneto, Xavier's former best friend and current arch-nemesis. When David is on the verge of ending Magneto's life, Xavier places himself between the two, and Legion inadvertently kills Xavier instead. Due to a "Grandfather paradox", Legion then ceases to exist as Xavier now died before Legion was even fathered.
Because of Xavier's sacrifice, Magneto comes to believe in his late friend's dream of peaceful co-existence between humans and mutants. Apocalypse, an immortal mutant who has been alive for centuries, was monitoring the fight. In this reality, he chooses this moment as the perfect time to begin his "survival of the fittest" genetic war, which doesn't happen in the regular Marvel Universe until ten years later.
In this timeline, Magneto establishes the X-Men, but not until after Apocalypse establishes himself as a major power. Apocalypse comes to rule all of North America, and initiates a worldwide genocidal campaign of "cullings" in which millions of humans die. The few that survive live in parts of Europe and Africa which were not devastated by nuclear weapons. Fleets of Sentinels are their only defense.
Meanwhile, the disturbance of the timeline leads to a crystallization wave of the M'Kraan Crystal that is heading toward Earth.
Magneto, as leader of the X-Men, leads a resistance movement against Apocalypse's forces. Early in the timeline, his daughter the Scarlet Witch is killed by one of Apocalypse's henchmen, Nemesis (later Holocaust). Next issue, Weapon X (Wolverine) and Jean Grey leave the X-Men to follow their own separate path. The true beginning of the Age of Apocalypse, however, is in the magazine X-Men Alpha, which will be described below.
Source :
http://en.wikipedia.org/wiki/Age_Of_ApocalypseYou can get the collections in TPBKs format :-
Age of Apocalypse Epic 1 ~ 4
Age of Apocalypse (limited series)
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