Magneto is one of the most complicated characters in the Marvel Universe. A sympathetic villain, Magneto has been through a lot of changes, switching sides between hero and villain. For years now, he's been a member of the X-Men, helping his old enemies in battle against the foes of the mutant race. One of the most powerful mutants on the planet, Magneto is a foe few heroes or villains want to face.
As daunting an antagonist as Magneto can be, he's had some pretty grievous losses over the years. While he's still not an enemy to be taken lightly, he isn't invincible and many of his defeats have been pretty bad.
10 Magneto's First Loss To The X-Men Is Still One Of His Most Embarrassing
Magneto's first appearance was in X-Men #1. Using his magnetic powers to attack a rocket launch site, Magneto proved his villainous bona fides right out the gate. While he was able to smack around the forces of the US military, he still ended up losing to a bunch of half trained teenagers, which is very embarrassing for someone like him.
Magneto's powers should have allowed him to easily destroy the original X-Men, who were nowhere near as powerful as they would become. Magneto's first defeat was a black mark on his record and remains one of his worst losses.
9 Quicksilver Got The Best Of Magneto In House Of M
House Of M had its problems as a story but it also contained one of Magneto's worst defeats. The Avengers and the X-Men, their memories returned by Wolverine and Layla Miller, went after Magneto, who they believed were behind Scarlet Witch's changing of the world. The battle would go badly for the heroes but Magneto would regain his memory and prepare to lash out at the person actually behind it all: Quicksilver.
Quicksilver would use his superspeed to easily beat Magneto, taking down the man he thought of as his father in order to protect Scarlet Witch.
8 Quicksilver Was The Hero Who Made The Difference In Apprehending Magneto In X-Men: Trial Of Magneto #1
One would think that when a person with superspeed battles someone who can control magnetism, the person with magnetism would have a chance in the fight, but Quicksilver flawlessly defeats Magneto constantly. The most recent example of this was in X-Men: Trial Of Magneto #1, where Quicksilver attacked Magneto for his suspected role in Scarlet Witch's death.
Magneto had just been beating on every mutant in X-Force and X-Factor when Quicksilver showed up and easily knocked out the mutant master of magnetism, before Northstar stopped Quicksilver from killing him. Apparently, Magneto's weakness is Quicksilver.
7 Magneto's Loss In Magneto War Saved The Earth But Was A Pyrrhic Victory For The X-Men
Magneto War saw Magneto making one of his most ambitious ever attacks on the world, as he decided to make good on an old threat of his and flip the magnetic poles of the Earth unless he got what he wanted: The island of Genosha. Battling against the X-Men and former ally Astra, Magneto would make a good acquitting for himself but ended up defeated by the X-Men, but not before killing his clone, Joseph.
The heroes' victory was futile, though, as the UN voted in favor of giving in to Magneto's demands, giving him control of the island of Genosha. Magneto would turn the island into a home for mutants but still took a kicking that day.
6 In X-Men: Schism, Magneto Got Beat By The New Inner Circle of The Hellfire Club
Magneto's time with the X-Men helped his win/loss record but there were still some rather embarrassing defeats. In X-Men: Schism, Magneto, Namor, Emma Frost, Colossus, and Iceman were attacked by the Hellfire Club at a museum opening, who were being led by a new Inner Circle of prepubescent genius humans. Magneto wasn't much help against them, as they had weapons specifically designed to defeat him.
Much like the rest of the X-Men at the opening, Magneto was completely outclassed by his young attackers, showing that power isn't everything.
5 In Avengers Vs. X-Men, Magneto Was Completely Ineffectual
Magneto would fight on the X-Men's side during the battle against the Avengers but was pretty much a non-entity in the fight. Going up against Iron Man should have been a piece of cake for him but Iron Man was prepared, embarrassing Magneto by being a man in a metal suit that could beat him. Things got worse from there.
Magneto became a cheerleader for the Phoenix Five but eventually stood against Cyclops and Emma Frost, which ended pretty badly for him. Later, in the battle against Dark Phoenix Cyclops, he would get smacked around even more.
4 Magneto Got Outclassed By The X-Men And Was Out Maneuvered By S.H.I.EL.D. In X-Men: Mutant Genesis
X-Men: Mutant Genesis chronicled Magneto's return to villainy as he battled the newly minted Blue Team of X-Men with the help of his new servants the Acolytes. Magneto and the Acolytes were able to get the best of the Blue Team, even taking control of them. The Gold Team arrived and was able to defeat Magneto, but S.H.I.E.L.D. had already played their own cards to end the conflict.
Targeting Asteroid M with a space based plasma beam, they prepared to destroy Magneto's base. The villain allowed the X-Men to evacuate before the weapon fired, destroying his base and killing most of his Acolytes, with him believed dead for a time after the attack.
3 Magneto Was Defeated By A Back-up Team Of X-Men In X-Men: Eve Of Destruction
Angry after Colossus died to cure the Legacy Virus, Magneto attacked the X-Mansion and took Professor X hostage in X-Men: Eve Of Destruction. The team was at their lowest ebb, with most of them away from the Mansion and unable to help. Wolverine, Cyclops, and Jean Grey would do their best to respond, with Wolverine and Cyclops sneaking into Genosha and Jean assembling a team of mutants for a frontal assault.
Together, they would hand Magneto a grievous defeat on his home soil, injuring him badly. Magneto would be left paralyzed after the battle, something that would doom Genosha in the near future.
2 Magneto Was Powerless To Stop The Genoshan Genocide
The day Cassandra Nova unleashed three Mega-Sentinels on Genosha was one of the worst days in mutant history and Magneto was powerless to stop it. Sixteen millions mutants died in minutes and Magneto was completely unable to do anything about it, having been gravely injured by the X-Men not long before and confined to a wheelchair.
To make it worse on Magneto, he would be one of the few survivors of the day. The mutant country of Genosha was everything he wanted for the mutant race and he lived long enough to witness its destruction but was unable to stop it.
1 Professor X Mindwiping Magneto Put Him Out Of Action For Years
Professor X and Magneto have always had a complicated relationship, one that came to a head in X-Men #25. After Magneto crippled the Earth with a massive electromagnetic pulse, the X-Men came after him and in the ensuing battle, Magneto ripped the adamantium from Wolverine's bones. In retaliation, Professor X would wipe Magneto's mind.
Magneto would remain a mindless husk for years afterwards but in a way, he would have the last laugh. Xavier's actions caused him to absorb Magneto's evil and become Onslaught, endangering the world and forcing the heroes to take him down.