The X-Men have dealt with plenty of bittersweet victories over their years of protecting a world that hates and fears them. But even though they might be doomed in the futures of Powers of X, the Marvel Universe's mutant heroes have never suffered as serious of a defeat as some alternate versions of them from across the multiverse.

Across Marvel's long-running anthology What If...?, Marvel explored several alternate realities where the X-Men were completely and utterly defeated. And in some cases, those defeats led to the end of a universe. Now, we're taking a look back at these fallen worlds to see how Marvel's mutants suffered their greatest defeats.

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WHAT IF THE X-MEN LOST INFERNO?

The '80s X-Men crossover "Inferno" saw Jean Grey's evil clone, Madelyne Pryor -- now going by the name Goblin Queen -- lead a demonic invasion of New York City. Although the X-Men were able to halt her plans in the 616-Marvel Universe, things didn't go according to plan in What If? Vol. 2 #6 by Danny Fingeroth and Ron Lim. In the core Marvel Universe, the demon Sym was knocked away from the battle. But in this world, Sym was able to return, which gave the Goblin Queen a much-needed advantage. The X-Men -- save for Wolverine, who Pryor corrupted with dark magics into her "pet" -- were all wiped out, and the Goblin Queen was able to sacrifice her son to permanently open a portal between Limbo and the mortal world. The Earth was quickly razed, with only a handful of heroes surviving the initial demon invasion and occupation.

Doctor Strange bands together with the last heroes -- Spider-Man, She-Hulk US Agent, Shadowcat, Thor and the Human Torch -- and sorcerors like Baron Mordo, but many are killed in an attack led by Wolverine and a corrupted Hulk. Only Doctor Strange, Shadowcat, Human Torc, and Mordo escape. They find Rachel Summers, which allows Doctor Strange to combine their powers to try and summon the Phoenix Force to Earth. However, Mordo betrays the heroes, and Human Torch has to sacrifice himself to buy them time. Shadowcat's death is enough to break Pryor's hold on Wolverine, who kills Mordo before dying himself. Pryor almost gets control of the Phoenix Force, but Sym -- who Pryor betrayed and killed -- possesses Logan's corpse and kills her in turn. Finally, Rachel uses the Phoenix to restore Earth to a more natural and demon free form.

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WHAT IF THE X-MEN LOST TO DRACULA?

The first time the X-Men encountered Dracula, he tried to turn Storm into a vampire. While he was foiled in the core Marvel Universe, Storm wasn't the only one bitten in What If? Vol. 2 #24 by Roy Thomas, RJM Lofficier, and Tom Morgan. Dracula was also able to turn Wolverine, Nightcrawler and Colossus, but Logan's willpower made him capable of resisting Dracula's control. With vampiric powers augmenting his natural skills, Wolverine kills Dracula to become the new Lord of Vampires. Corrupted by undead malevolence, Wolverine and his followers quickly spread. Magneto, the New Mutants, the Hellfire Club, Freedom Force and the Morlocks are all added to the army of undead mutants, and the vampiric plague spreads across all of New York after Juggernaut kills Doctor Strange.

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Some heroes are converted, while others are outright killed. Only Captain America, Iron Man and a handful of Avengers who were out of the city at the time avoid the vampire army. New York is locked down by the US military and left to fend for itself. The spirit of Doctor Strange finds the Punisher -- one of the last humans in the city -- and guides him to the Eye of Agamotto and the Cloak of Levitation. Punisher soon becomes a one-man -army, bringing down many of the vampiric X-Men. Next, Punisher confronts Wolverine next, and their duel turns out to be fairly evenly matched. However, Shadowcat ends up accidentally getting involved and is slain by Punisher. Wolverine kills him but Doctor Strange convinces a briefly human Logan to use the Montesi Formula and destroy all vampires on the planet, including himself.

WHAT IF THE X-MEN LOST TO SHARD?

In most realities, Bishop makes his way back to the past after the death of his sister Shard. But in the reality introduced in What If? Vol. 2 #84 by Gerard Jones and Mark Pacella, it was Bishop who was killed by Trevor Fitzroy. This meant that the more aggressive Shard went into the past to find him, and she also worked with the X-Men when she first arrived in the past. While the X-Men helped her corner Fitzroy, she was able to kill him in front of her shocked teammates. Less committed to Xavier's dream than Bishop was, she becomes convinced that working with the government from the beginning is the only way to avoid attacks on mutants. Shard leaves the X-Men to try and build a modern equivalent of the XSE, the police force she and Bishop belonged to in the future.

Shard ends up outfitted with new technology courtesy of Grayson Creed and tries to assassinate Magneto, only to be stopped by the X-Men. But when she makes another effort to kill Magneto, she's successful and able to murder him. The X-Men confront Shard over her actions, and Storm tries to bring her down, but Shard ends up killing Storm in their fight. Shard convinces herself that the X-Men are in the wrong, and that Storm's death wasn't her fault. She goes on to lead her XSE in a bid to force human and mutant coexistence. Her efforts to create peace failed spectacularly, as humanity sees her war against evil mutants as an inspiration to wipe out ALL mutants, which leads to a purge of the species and Shard being held up as a martyr for that cause.

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WHAT IF THE X-MEN LOST TO JUGGERNAUT?

Juggernaut has always been a consistent threat to the X-Men, but in Jorge Gonzales and James Calafiore's What If? Vol. 2 #94, the ramifications of his potential victory was explored. In this world, Juggernaut wiped out Xavier and most of his first-class of X-Men. However, this meant the X-Men weren't around to fight against the Sentinels and expose their plans to the world. As a result, the Sentinel Program was able to operate in secret, eventually killing the other superheroes and even filling the world with radiation that was lethal to humans and mutants alike. Thanks to his powers, Juggernaut was unaffected by the radiation and went to war with the Sentinels but quickly became the only person left on the planet, left fending for himself against the last few Sentinels.

Years later, Juggernaut found himself confronting a dying Magneto who revealed the truth behind Juggernaut's mistake and battled him with the remains of the Sentinels. He even reveals that while he was in space, he encountered a device that could look into alternate realities, including multiple ones where the X-Men didn't die and were able to prevent the Sentinels from wiping out all life on Earth. As Magneto dies, Juggernaut finds Iceman, the last of the X-Men. Despite Iceman's pleadings, Juggernaut breaks through an ice wall to find the last of humanity, which is led by the Brotherhood of Mutants in peaceful coexistence. But in doing so, Juggernaut spreads the radiation to the community, dooming them all. They force Juggernaut to leave so they can die in peace, and Juggernaut walks away a broken man left alone in the entire world.

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WHAT IF THE X-MEN LOST TO DANGER?

In one of the stories from What If? Astonishing X-Men #1 by Matteo Casali and Mike Getty, the Astonishing X-Men found themselves confronted by Danger. The living personification of the Danger Room, the machine grew to hate the mutants that she helped train. But when she turned against the X-Men in the core Marvel Universe, the safeguards in her system against killing helpt her from wiping them out. But in one world, Ultron discovered the birth of Danger while attacking the Runaways. Deciding that Danger was a far more enticing possibility than Victor Mancha working with him. Ultron quickly killed Victor and the Runaways and traveled to Westchester.

In love with Danger, Ultron proves his dedication to her by slaughtering the students of the Xavier Institute. The two combine their programming, which removes Danger's inability to kill the X-Men. The pair then slaughter all of the X-Men present and execute Charles Xavier for having used Danger as a training tool. With that, Ultron and Danger make their way into the cosmos, towards the Shi'ar corner of the galaxy that Danger technically hails from. The Watcher of this reality observes that together, the pair will be able to infest and overtake the Shi'ar infrastructure, eventually leading to the pair of them to fuse with the Phalanx and become the dominant form of life in the universe.

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