Story is split into several arcs beginning with Legion Quest

Begins with Legion waking up from a coma after an encounter with Shadow King and decides that the best way to achieve his father Xavier’s goal of world peace is by going back in time and eliminating Magneto

Legion goes back in time, psionically taking Storm, Psylocke, Iceman and Bishop with him as well after confronting Legion in the present

Xavier sends Cable’s psyche to the past where Legion is, to help the X-men remember their mission to stop him

Legion attempts to kill Magneto but kills Xavier instead when he sacrifices himself 

Creates a ripple effect in time- Legion is no longer born, the X-men are never formed, and the Nexus of All Realities within the M’kraan Crystal is affected rearranging time and reality itself

The only one not affected is Bishop because he is a time-traveler who would go on to tell the resistance of the new timeline (led by Magneto) that it is not the real one

Magneto is the leader of the X-men, Rogue is his lover, and they have a son named Charles

Beast, Cyclops, and Havok work for Apocalypse, until Cyclops defects later on and joins the Resistance 

Cyclops blew off Wolverine’s hand and Wolverine cut out one of Cyclops’ eyes during a past battle 

Different story threads include Gambit and his Externals going to the Shi’ar empire to retrieve a shard of the M’kraan Crystal on orders from Magneto who, despite not knowing Bishop, feels he must take the chance of trusting him for a better world and sends Gambit to find it to prove if Bishop’s claims are true which are testified to by the M’kraan guardian Jahf

Likewise, Nightcrawler is sent by Magneto to Avalon (mutant haven) to seek out Destiny who’s precognitive powers could confirm Bishop’s claims which they do

Apocalypse’s four horsemen in this reality are Jamie Braddock, Abyss, Mr. Sinister, and his son Holocaust

Mr. Sinister poses as Nathaniel Essex and infiltrates Forge’s team which includes the mutant Nate Grey (alternate Cable) who is a genetic experiment created by Sinister as the ultimate weapon against Apocalypse. He’s created from Jean and Cyclops’ genes

Sinister is killed by Nate who had a close bond with Forge after Sinister kills Forge

Magneto ultimately kills Apocalypse by magnetically ripping him in half

Havok kills Jean and Wolverine kills Havok

Bishop, Destiny, and Illyana Rasputin enter the M’kraan Crystal after Apocalypse is defeated. Illyana and Destiny use their magic and precognitive powers respectively to send Bishop to where Legion killed Magneto and stops him thus erasing Apocalypse’s reality 

This reality is known as Earth-295