Marvel was known as the House of Ideas for a long time, bringing new sensibilities to superhero comics. A fun one has always been when supervillains switch sides. Many times over the years, villains have become heroes or helped save the day in some way. These face turns, face being from the wrestling term for the hero "babyface," have been very memorable for fans, giving them new stories.

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Sometimes, these turns last; other times, they're just for a moment. They've added dimension to the villains and their conflicts with the heroes. These face turns have been a lot of fun in some cases, taking stories in unprecedented directions.

10 Loki Returned To Life As A Hero

Marvel Comics' Loki in Young Avengers

Many Marvel villains are charismatic, and few can match Loki on that count. The God of Mischief is known for being a chameleon in many ways, using his powers and cunning to mess with his foes. This hasn't always worked very well, and he's ended up dying several times. He always returns, and one return saw him come back as a teenager with a new lease on life.

This young Loki joined the Young Avengers, becoming a hero. He "grew" up, taking his adult body back but stayed more heroic for a time, working with his brother and helping fight for Asgard. Loki as a hero was an interesting time for the character.

9 The Sentry Took Control Back From The Void, Which Allowed The Heroes To Win

Marvel Comics' The Sentry surrounded by a storm

During Norman Osborn's Dark Reign, the villain worked to ingratiate himself with the Sentry. He knew the hero's secret - that he had the Void inside him, a monstrous villain that everyone feared. He manipulated the mentally fragile Sentry, using him to get the Void to help the Dark Avengers in their battles.

As time went on, the Void got more and more powerful. This came to a head during the Siege of Asgard when the Sentry killed Ares and leveled massive portions of the city of the gods on his own. The Void took complete control toward the end of the conflict, killing Loki and smacking around the heroes. When all seemed lost, the Sentry took control again, powering down and telling Thor to kill him before the Void came back. The God of Thunder obliged, and the day was saved.

8 Galactus Became The Lifebringer

Marvel Comics' Galactus as the Lifebringer gestures forward

Galactus is a constant of the universe and has been since the beginning. The World Devourer has traveled the cosmos for eons, destroying worlds and taking their energy. However, after the Incursions and the restoration of the universe, the Ultimates decided to cure Galactus's hunger. They forced him into his Incubator, and he became the Lifebringer.

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Galactus joined the Ultimates, and he traveled the universe restoring worlds. Seeing Galactus as a force for life instead of death was a huge change for everyone. His trademark purple became yellow, his powers changed, and for a time, the coming of Galactus wasn't an occasion for fear.

7 Sabretooth Became A Hero In The Age Of Apocalypse

Sabretooth crouching on top of Nemesis in Age of Apocalypse

Sabretooth has starred in some memorable comics, with The Age Of Apocalypse's Astonishing X-Men #1-4 shocking readers. In it, Sabretooth wasn't a villain but a member of the X-Men, working with Wild Child and looking out for young mutant Blink. He was basically the Wolverine of the alternate universe team.

Sabretooth had worked with the X-Men before in the 616 universe, most recently at the time during "The Phalanx Covenant" storyline, but to see him so heroic was a great change. AoA Sabretooth is probably the most unequivocally beloved version of the character, as well as the most disparate version of the character.

6 Thanos Spent A Portion Of The '90s Being Heroic

Happy Thanos on the farm Marvel Comics

Infinity Gauntlet was a game changer, bringing Thanos back to prominence. The ending also changed the character completely, as he decided to stop being a genocidal monster. Then came Infinity War, when Thanos helped fight against the Magus, saving the universe. He'd go on to help during Infinity Crusade and was instrumental in defeating Thor in the grips of Warrior Madness.

It was even revealed that Thanos had held the Reality Gem in secret for years after the Living Tribunal forced Adam Warlock to separate the Infinity Gauntlet. It was an interesting time in Thanos's history, as the nihilist gave way to a being who was at peace with his place in the universe.

5 Norman Osborn's Time As Iron Patriot Was A Big Change In Many Ways

Marvel Comics' Norman Osborn as Iron Patriot

Some Marvel villains deserved to win their battles, something that Norman Osborn proved after the superhero civil war. Osborn rose to power working for Iron Man, commanded the Thunderbolts for the Initiative, and then killed the Skrull Queen Veranke. After this, he was given the keys to the kingdom, taking the lead of the Initiative, SHIELD, and the Avengers.

As Iron Patriot, Osborn led the Dark Avengers and saved the world several times. His Dark Reign wasn't a complete face turn in many ways, as he was working to keep power for himself. He lost it all because of his hubris, but he defeated both Morgan Le Fay and the Molecule Man, which isn't too shabby.

4 Apocalypse Changed Completely On Krakoa

Marvel Comics' Apocalypse looking straight ahead threateningly

Many Marvel villains are killers, with Apocalypse spending millennia killing all those he considered weak. However, when offered the amnesty of Krakoa, Apocalypse embraced it. He saw that mutants together were strong and that this new nation was a part of his dream and his ultimate purpose.

Apocalypse's Darwinist beliefs were born of trying to create a powerful enough army to survive the next invasion of Amenth, a realm of powerful demons from Otherworld. When that invasion happened, Apocalypse was front and center during the battle. He was a stalwart warrior and helped sway the tide of the battle, a crucial part of Krakoa's victory.

3 The Masters Of Evil Becoming The Thunderbolts Was A Huge Moment In Marvel History

An image of Kurt Busiek's Thunderbolts from Marvel Comics

Baron Zemo is a tactical mastermind, but his best scheme was the Thunderbolts. After the Avengers and Fantastic Four were thought dead in the battle with Onslaught, Zemo gathered Moonstone, Goliath, the Beetle, Screaming Mimi, and Fixer,coming up with a plan to take advantage of the situation. He posed as Citizen V, and the others were rechristened Meteorite, Atlas, MACH-1, Songbird, and Techno. Thus was born the Thunderbolts.

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Zemo's plan was to get in the public's good graces and strike, but Meteorite, Atlas, Songbird, and MACH-1 liked being heroes. Zemo's plan was foiled when the Avengers returned, but the whole Thunderbolts idea was an inspired plan, to say the least.

2 Doctor Doom Turned Over A New Leaf After Secret Wars And Became The Infamous Iron Man

Doctor Doom surrounded by energy as the Infamous Iron Man

Doctor Doom has always been a ruthless Marvel villain, but after his stint as God Emperor during Secret Wars and the mercy shown to him by Reed Richards, he decided that he wanted to change. After Iron Man was beaten into a coma by Captain Marvel, Doom decided to pay homage to his old foe, becoming the Infamous Iron Man.

While the Thing and SHIELD didn't believe he had changed, Doom had truly turned over a new leaf. He battled Fantastic Four villains to make up for the team not being around and stopped a scheme by Mephisto. He even went on a multiversal jaunt with Human Torch and the Thing. He'd eventually become a villain again, but his time as a hero was memorable.

1 Magneto Joined The X-Men And Became A Mutant Leader

Magneto and Xavier walk through Krakoa in Marvel Comics

There are some unlikely Marvel heroes, with Magneto being foremost among them. Once the X-Men's greatest enemy, he joined up with the team once before while Xavier was in the Shi'Ar Empire, but eventually went back to being a villain. After M-Day, Magneto was powerless, but upon regaining his powers, he joined the X-Men.

Since then, Magneto has been a stalwart member of the team. He's all about protecting the mutant race, and he's been able to do that with his former foes. He also spent years helping Xavier and Moira MacTaggert set up the mutant nation of Krakoa, becoming a leader in that new mutant nation, as well as on Arakko.

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