Charles Xavier is the founder of the X-Men and -- despite some morally questionable actions -- has often been held up as a major force for good. His status isn't limited to mutantkind, either; in the Marvel Universe as a whole, he's often seen as a good guy. However, in some universes, Professor X is deadly, dangerous and villainous.

Here are some of the most fearsome and villainous versions of Charles Xavier from across the Marvel multiverse.

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The Juggernaut

On Earth-905, it was Charles Xavier and not his step-brother Cain Marko who touched the Gem of Cyttorak and became the unstoppable Juggernaut. Trapped digging himself out from under a collapsed cavern for years, the Xavier of this world never formed the X-Men -- leaving Magneto to define human opinion on mutants with his violent actions.

Magneto eventually rallied an entire army to attack the United Nations, only to be stopped by the finally freed Xavier. Xavier announced the protection of all mutants and pushed Magneto into exile. The Sentinel program was single-handily defeated by Juggernaut's strength, while the superhero community was defeated (and in some cases even cured of their abilities) by Xavier's enhanced psychic powers, which gave him access to the greatest minds on Earth.

Nuclear weapons were deployed against the mutants as a last resort, but Xavier quickly figured out how to stabilize the planet. The excess radiation also helped bolster the mutant population, leading to a new generation of mutants quickly taking over the world.

Seeing the mutant race become just as cruel as humans were, Xavier's lieutenant Cyclops allied with Magneto and Marko to bring Xavier down. In the end, they lured Xavier to Magneto's base in outer space and sent him spiraling into the cosmos, unable to stop his momentum. With the powers of the Juggernaut making him all but immortal, it's likely he never stopped flying through the universe.

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Shadow-X

After briefly being bound together psychically, the Earth-616 Psylocke and Shadow King were separated when she was killed during the events of X-Treme X-Men Vol. 1. Untethered to just one reality, Shadow King landed in a world with a younger Charles Xavier.

This version of Xavier quickly had his mind shattered by Shadow King and was corrupted into his puppet. He soon became a villain, corrupting his students into servants and quickly wiping out most of the heroes of that reality. When House of M temporarily weakened the dimensional barriers that separate realities, Shadow King returned alongside his corrupted Xavier and his X-Men.

After arriving in the core Marvel Universe, Shadow-X and his dark X-Men tried to expand his influence in London. Thanks to the intervention of Excalibur, Shadow-X was held at bay. Although he camesclose to corrupting the core-universe Kitty Pryde and Rachel Summers, Juggernaut and Pete Wisdom were able to hit him hard enough for Rachel to gain an advantage in their psychic duel and defeat Shadow-X while the rest of her allies defeated his students.

The villainous versions of the X-Men were held prisoner by MI-13 until Albion (a despotic alternate reality version of Captain Britain) attacked the Earth-616 Captain Britain in a bid to weaken Roma's multiversal power. Shadow-X and his evil X-Men fought alongside Excalibur -- genuinely enjoying the bloodshed -- but were all killed in the battle.

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Fascist Xavier & Witch-King Xavier

X-Treme X-Men Vol. 2 focused on a team of multiversal mutants hunting down 10 evil versions of Charles Xavier across the multiverse before they could cause destruction and devastation to other realities.

One such Xavier hailed from Earth-16111, a world turned into the realm of Gha-No-Shah. While other realities (including the core Marvel Universe) briefly had to deal with such an incursion, this world was fully transformed. Ruled over by Xavier the Witch-King, it quickly filled with cruel goblins and mutated beasts, with Xavier operating as a fantasy dark lord -- even eating the Bamfs/Crawlers of his world.

The X-Treme X-Men defeated him, albeit at the cost of a war-tested Dazzler, who sacrificed herself. However, the Witch-King survived within the mind of the Xavier Head, who served as the guide to the team.

Their next trip was to Earth-13410, where Charles Xavier was born before the events of the Second World War and helped create a fascist government within Britain. This meant the nation didn't side with the Allies and instead gave the Axis Powers the edge they needed to win the war. Xavier then turned on his "allies" and killed them.

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Just as control of the world was all but handed to him, the Atlanteans took the opportunity to declare war on the surface-world by creating massive tidal waves. Namor -- who in this reality was half-Japanese and had been a member of the Japanese Imperial machine -- went to Atlantis to sue for peace, only to watch Xavier destroy it and its people. This set off a war between Xavier and Namor that destroyed much of the Earth.

The X-Treme X-Men were tasked with bringing down Xavier while reluctantly saving his "innocent" citizens. Along the way, they discovered Xavier's forces had been keeping a group of Black men and women as slaves, further solidifying the X-Treme X-Men's plans to bring down both the murderous Namor and Xavier.

Although they helped Xavier wound Namor, Dazzler mortally wounded Xavier and left him open to be beheaded by Namor. Despite their apparent victory, this fascist Xavier was resurrected and restored by the Witch-King Xavier, who forced the Xavier Head to teleport them to another reality. On Earth-13812, they were able to build the interdimensional rift they'd been feared of unleashing, bringing the Exterminators to that reality. Instead of gratitude, the Exterminators killed both Xaviers with ease.

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