With Professor Charles Xavier dead and Magneto taking over for the Marvel Comics superhero team, Marvel created the "Age of Apocalypse." In this alternate universe, members of The X-Men were not acting all like themselves because the timeline had changed so drastically. Because he was a time-traveler, the mutant known as Bishop was stranded in a dystopian future, searching for hope among the devastation left behind by the tyrannical ruler known as Apocalypse. With a single chance to reset things right, Bishop realizes desperate measures and ultimate sacrifices had to be made.

David Charles Haller, the mutant son of Charles Xavier and Gabrielle Haller, woke up from his coma with a devious plan. Calling himself Legion, David thought he could make Charles' dream for peace and unity come true if he murdered Erik Lehnsherr in the past. Just when David was about to deliver the fatal blow, Charles stepped in for his best friend and was struck dead. With his father dead, David was erased from the timestream and Erik was left alone to carry on Charles' dream by creating the X-Men.

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10 10. Bishop's Return

After failing to stop Legion from killing Xavier, Bishop had been living in exile for many years, haunted by his own mistake. Upon his unexpected return in X-Men Alpha #1, Bishop has now physically and mentally changed. Traumatized by his failure, Bishop has shaved his entire head and got rid of the beard, making himself barely recognizable. Because he is a time-traveler, Bishop has memories of the other timeline and just sees things that are completely wrong. This is a truly heartbreaking portrayal to see how far Bishop has fallen from his former self.

9 9. Skin vs. Husk

In the pages of Generation X, Angelo Espinosa, aka Skin, and Paige Guthrie, also known as Husk, were the best of friends. The pair would end up playing crossword puzzles as a way to outwit each other. The two were always constantly teasing each other. Unfortunately, their friendship no longer exists in Generation Next.

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During an intense training session, Husk reveals just how cold-hearted she really is and refuses to bail out Skin when he asks for help. This version of Husk has no sense of loyalty and could care less about what happens to her teammates.

8 8. Death of Forge

In this alternate version of Cable, Nate Grey was genetically engineered by Sinister as a powerful weapon to destroy Apocalypse. The fight against Apocalypse forced the super-genius Forge to replace his eye, arms, and legs with cybernetic implants. While protecting Nate, Forge died a horrible death during his fatal battle against Essex, one of Apocalypse's henchmen. Unable to control his telepathic powers, Nate could feel Forge's pain as Essex tore him limb from limb. Having lost his only father figure, Nate held what was left of Forge's destroyed body in his arms.

7 7. Death of Scarlet Witch

In X-Men Chronicles #1, Wanda Maximoff, also known as Scarlet Witch, is an official member of the mutant superhero team. While Magneto and the X-Men are fighting Apocalypse and his Horsemen, Wanda volunteers to watch other the children at their special school.

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Magneto realizes too late that this was all a distraction as Apocalypse actually sent Nemesis to destroy the school. While Rogue rescues the school children, Wanda ends up fighting to the death against Nemesis. With just a few seconds to live, Wanda asks Rogue to promise that she will take care of her father.

6 6. Rogue Cannot Touch Her Own Son

In this alternate universe, Rogue chose to stay with Magneto, instead of former thief Remy Labeau, also known as Gambit. Because Magneto can use his magnetic powers to touch Rogue, she doesn't have to worry about absorbing his life force. In the pages of X-Men Alpha #1, readers discover Magneto named his first-born son after his best friend. After tucking in young Charles to sleep and saying prayers with him, there is an immense sadness in Rogue. Unable to take off her gloves, Rogue wonders if her own son will ever feel the warm embrace of his loving mother.

5 5. Colossus Kills Kitty

According to Shi'ar legends, the M'Kraan Crystal is considered to be nexus of all realities. Though untrained, Illyana Rasputin, Colossus' little sister, has the powers of a sorceress to command the M'Kraan Crystal. Bishop believes Illyana is integral in summoning the M'Kraan Crystal to undo Xavier's murder.

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After Bishop and Illyana disappear into the M'Kraan Crystal, Colossus goes crazy and shatters Iceman. Kitty Pryde, also known as Shadowcat, thinks Colossus will stop because he loves her. During his stampede, Colossus doesn't stop and ends up stomping over Kitty, crushing her head.

4 4. Brother vs. Brother

Alex and Scott Summers were raised at the orphanage run by Nathaniel Essex, also known as Sinister. Though he raised the two siblings like they were his own children, Sinister had always treated Cyclops like his favorite. Because Sinister demonstrated his favoritism for Scott over Alex, this drove a huge wedge between Havok and Cyclops. As if it were his only purpose in life, Havok wanted to prove that he was truly better than Cyclops. Rather than help save the world from nuclear oblivion, Havok used his mutant powers to kill his own brother.

3 3. She's No Phoenix

In this alternate universe, Jean Grey chose to be with Wolverine, instead of Cyclops. In order to keep the nuclear warheads from striking, Jean Grey was using her telepathic powers at full force to keep them in mid-air. Just when her plan was actually working, Havok struck Jean from behind and killed her.

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There was no Phoenix Force to come in and bring Jean back from the dead. After driving his adamantium claws through Havok's chest, Wolverine held Jean in his arms as she used her last breath to tell him that she loved him.

2 2. The Nuclear Apocalypse

In the closing pages of X-Men: Omega #1, the world is still going to end. After splitting apart Apocalypse with his bare magnetic hands, Erik decides to watch the world burn with his family. Embracing death, Magneto has no idea if Bishop went back in time and saved his best friend. While holding his son tightly, Magneto tells his wife, Rogue, that he wouldn't have changed anything. As the nuclear warheads hit the ground and unleash hell on earth, Magneto says he would always choose to follow in the path of Xavier's dream.

1 1. Bishop's Last Words

In the climax of X-Men: Omega #1, Bishop finds himself traveling back in time, just mere moments before David kills Xavier. After Bishop fights his other self, he saves Xavier and steps in when Legion strikes. While Bishop absorbs his powers, Legion witnesses the events of the alternate universe and feels unbelievably regretful. Realizing the mistake he had made, David asks for forgiveness but Bishop isn't going to let him off easy. As the timeline resets itself, Bishop coldly reminds David that he ruined his father's dream and Xavier would not be proud of him.

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