One of the earliest mutants on Earth, Apocalypse, and his longtime ally Sinister, witnessed the first televised confirmation of super-powered beings when Legion accidentally murdered his father, Charles Xavier. A fervent adherent to the philosophy of survival of the fittest, Apocalypse used this moment as the catalyst to launch his war against humanity. With Xavier dead and Apocalypse beginning his conquest a full decade earlier than in Earth-616, there was no force capable of opposing him. Though Magneto would eventually form a resistance known as the X-Men, Apocalypse had already consolidated power through his elite lieutenants, the Horsemen. Initially numerous, the Horsemen were ultimately reduced to four after Apocalypse conquered North America and declared the War of Secession, a brutal internal conflict he allowed to rage until only the strongest remained.
Over time, Apocalypse crushed most of the world’s governments, leaving only two meaningful threats to his dominion: the X-Men and the Human High Council in Europe. While publicly negotiating a peace treaty between mutants and humans—the Kelly Pact, which promised coexistence and the abolition of genetic testing—Apocalypse secretly prepared a devastating surprise attack. The treaty was a deception, as he never intended to honor its terms. Unbeknownst to him, however, his empire was already unraveling. Sinister had abandoned him, his most powerful Horseman, Mikhail, had gone rogue, and Abyss and Holocaust were consumed by personal conflicts that blinded them to the larger war. Apocalypse had surrounded himself with immense power, but little loyalty or reliability.
Apocalypse eventually discovered Magneto’s location and captured him. At the same time, the X-Ternal traitor Strong Guy stole the M’Kraan Crystal, which Magneto intended to use to alter history and prevent the Age of Apocalypse altogether. The X-Men launched a direct assault by teleporting into Apocalypse’s New York City stronghold. During the chaos, Magneto was freed by X-Man, Sinister’s ultimate genetic creation. In the final confrontation, Magneto unleashed the full extent of his magnetic abilities, tearing Apocalypse apart and bringing his reign to an end.
NOTE: Information from The Official Handbook of the Marvel Universe: X-Men - Age of Apocalypse 2005
