The X-Men are Marvel‘s golden children; they started at the bottom, and have become extremely popular, both in the comics and in pop culture in general. Over the years, fans have seen the team grow in numerous ways. They’ve become the rule; as they got popular, more and more creators tried to make their work like them. However, not everything in the X-books came from the X-books; they were often groundbreaking, but not completely, and they took some of their ideas from other teams. One of the most fruitful of these ideas was villains joining the team. The X-Men weren’t the first ones to bring villains to the team, but they’ve become the best.
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The X-Men have the best villains ever, and some of the greatest have ended up on the team. These villains have proven popular enough with readers to deserve more spotlight, and that spotlight came would come on the team they fought. These seven Marvel villains have all become X-Men, each of their tenures with the group unique.
7) Cyclops

Cyclops is the X-Men’s greatest leader, and is basically the mutant Captain America. While he’s best known as a hero, some would say THE hero of the X-Men, he has been a villain, most notably in Marvel’s underrated event Avengers vs. X-Men. He gained a portion of the Phoenix Force and it drove him mad. By the end of the story, he had become the Dark Phoenix, forcing the Avengers and X-Men to team up to defeat him. They did, the Phoenix Force left him, and he was imprisoned. He ended up escaping and starting his own team of X-Men. That’s a villain becoming an X-Man, folks, even if the whole thing is a technicality.
6) Lady Mastermind

Mastermind was one of the first X-Men villains, a member of the Brotherhood of Evil Mutants with illusion based mind control powers. He had a daughter, and she had the same powers as him, so she became Lady Mastermind. She ended up joining Rogue’s rapid response X-Men team after House of M, but she wasn’t there in good conscience, because she wanted to be good. She was working for Mister Sinister to destroy the team from within. She’d eventually betray them and join the new Marauders to battle them.
5) Kid Omega

Quentin Quire was sent to the Xavier Institute when his psionic powers developed. He wasn’t one of the cool kids, and then he found out that his parents weren’t actually his; he was adopted. This drove him off the deep end, and he became a troublemaker, bringing together a gang and embracing mutant supremacy. He tried to attack humans on the school’s first open day, but was defeated by the Stepford Cuckoos, who defeated his mental powers at the cost of Sophie, who he had a crush on. He became a being of psionic energy, but was eventually reincorporated. He tried to attack the UN, got beat by Cyclops and Wolverine, and was eventually forcefully enrolled in the Jean Grey School by Logan. Since, he’s been a student, a member of Generation X and X-Force, and worked with the X-Men. He’s still a bit edgy, but he’s grown.
4) Mystique

It doesn’t seem like it to some, but Mystique is actually an underrated character. She was a main villain of Claremont’s first run for most of the ’80s, leading the Brotherhood of Evil Mutants/Freedom Force in their most recognizable form (her, Destiny, Blob, Pyro, and Avalanche, with members like Rogue, Sabre, Crimson Commando, and Spiral joining up at times). In the ’90s, she would go through some mental issues, join the government version of X-Factor, and continue to battle the X-Men at times. Her first time on the team was when she posed as Foxx, a mutant designed to make Gambit have sex with her so Rogue wouldn’t love him. She’d later end up on the rapid response team, betraying them for Sinister. She was basically an X-Man during the Krakoa Era, as well, and it was revealed that there was a time that she was working for Xavier behind the scenes in the past (and in the present of the Krakoa Era), so it could be said she’s been an X-Man longer than anything else.
3) Sabretooth

So, technically, Sabretooth is one of the first Avengers chronologically, so him being an X-Man isn’t terribly surprising. He battled them for years, mostly to get the chance to slap around Wolverine and kill lots of people, and eventually started working with the telepath Birdy. She was able to give him the “glow” with her powers, which fed his bloodlust somehow and made him less monstrous. She was killed by his and Mystique’s son Graydon Creed, so he went mad and the X-Men took him prisoner, trying to help him through it (in case you were wondering, this was after Wolverine lost his adamantium, so he wasn’t there for this; however, it’s funny to think that Marvel used Creed as a Logan substitute). He had to wear special manacles that stopped him from attacking the X-Men, and would help defeat the Phalanx. In “The Age of Apocalypse” universe, he was a member of the X-Men. He joined X-Factor in the ’90s, and would later also join the rapid response team, although Wolverine went after him, so he wasn’t around when the betrayal went down. He was morally reversed in AXIS, and joined Magneto’s team of X-Men during the Inhumans push years, but has since gone back to evil.
2) Rogue

When Rogue’s powers manifested she was kissing her first boyfriend. She put him in a coma and was run out of town, eventually being found by Mystique and Destiny. The couple raised her and trained her, making her a member of the Brotherhood of Evil Mutants. The young mutant trounced the Avengers, using their powers against them, but held on too long to Ms. Marvel. The memory absorption broke her brain, and the X-Men took her in to help her. Since then, she’s become a leader of the team, an Avengers leader, and one of the most popular X-Men of all time. Everyone loves Rogue.
1) Magneto

Magneto’s morality has often changed over the years, and he’s since become one of the most popular X-Men. He was the team’s first villain, the founder of the Brotherhood of Evil Mutants, and his pragmatic vision of humanity’s evil made him Xavier’s ideological opposite. However, as the years has gone on, he’s opened himself to his friend’s teaching and joined the X-Men. The first time he took Xavier’s place was when Charles went to be healed by Lilandra, helping train the New Mutants. He’d join again years later after a return to villainy after he regained his powers, which were taken by Scarlet Witch in House of M, helping to protect mutantkind and follow the orders of Cyclops. He’s been with X-Men teams ever since, leading them at times, and becoming a world leader (on two different worlds) during the Krakoa Era.
What are your favorite Marvel villains turned X-Men? Leave a comment in the comment section below and join the conversation on the ComicBook Forums!








