“Age of Apocalypse” is a 1995–1996 comic book crossover story line published in the X-Men franchise of books by Marvel Comics. The Age of Apocalypse briefly replaced the universe of Earth-616 and had ramifications in the main Marvel Comics universe when the original timeline was restored. It was later retconned as having occurred in the alternate universe of Earth-295.
Legion (David Haller), a psionic mutant on Earth and son of Professor Charles Xavier, travels back in time with the intention of killing Magneto.
However, Legion traveled to a time when Magneto and Xavier were still friends. As Xavier dies trying to protect Magneto, Legion vanishes, and a new timeline is created. The only person aware of how history has changed is Bishop, a time traveling mutant who followed Legion.
Because of Xavier’s sacrifice, Magneto comes to believe in his late friend’s dream of a peaceful coexistence between humans and mutants.
Apocalypse, an immortal mutant villain, was monitoring the fight. He chooses this moment as the perfect time to begin his world conquest, which did not happen in the mainstream Marvel universe for another ten years.
Magneto assembles the X-Men just as Apocalypse begins his war. Despite the X-Men’s resistance, Apocalypse conquers all of North America and eventually mutants are considered the ruling class. Apocalypse also initiated a genocidal campaign called “cullings” killing millions of humans. To further ensure that no one was left to challenge him or undo the circumstances that led to his reign, he had everyone with telepathic or chronal abilities hunted down.
Meanwhile, the changes in the timeline result in a destructive crystallization wave created by the M’Kraan Crystal.
The Amazing X-Men consist of team leader Quicksilver and Storm, Dazzler, Banshee, Iceman, and Exodus. The team is sent to Maine by Magneto to aid in the evacuation of humanity to Europe. During this mission, the team fights Apocalypse’s Brotherhood of Chaos, as well as the Horseman Abyss, who is defeated (but not killed) by Banshee. During their absence from the Xavier Mansion, Magneto and Bishop are attacked by Apocalypse himself, who captures them both.
Fulfilling their mission, Quicksilver splits up his team to help the other X-Men: sending Iceman to rendezvous with Rogue’s team (the Astonishing X-Men) and Dazzler and Exodus to find Magneto’s son, Charles. Finally, Quicksilver, Storm, and Banshee go to rescue Bishop, who is in the hands of the Madri, Apocalypse’s priests.