For over 80 years, Marvel Comics has been creating a vast worldfull of iconic characters. These characters have become synonymous with a generation. And within this universe, even the greatest and most fearsome villains have found a path towards redemption.

Time and again, we have seen that beneath the surface of violence and villainy lies the potential for change. Nowhere is this potential more profound and visible than in Marvel baddies. So many supervillains havediscovered a capacity for good, left their life of crime behind and become revered heroes. This transition is both genuine and exciting.

In this list, we take a look at 20 Marvel characters who experienced a change of heart. From vengeful adversaries like Namor and Magneto to reluctant villains like Quicksilver and Hawkeye, the reformed histories of these characters are testament to the power of free will and compassion beyond natural instinct.

The First Non-Mutant X-Man

First appearing inX-Men #19, Calvin Rankin was an ordinary individual who was exposed to one of his father’s dangerous lab experiments, following which he gained the powers of duplicating the abilities of nearby superheroes. AsMimic, he could not only copy superpowers but also a human’s personality, their skills and intelligence. While initially using his gifts for criminal intentions, Mimic soon found himself joining the original X-Men as the first X-Man who was not a mutant.

Mimic’s hero turn was inX-Men #27, which was written by Roy Thomas. Through cooperative missions with the X-Men, he began developing a sense of purpose. He proved instrumental in defeating the Puppet Master, who was trying to control and manipulate him. But the team’s fateful run-in with Super-Adaptoid left Mimic depowered almost two issues later.

19Doctor Octopus

One of the Coolest Spider-Man Runs

One of the most surprising villain-turned-hero, one that nobody saw coming, Otto Octavious debuted inAmazing Spider-Man #3back in 1963. As a twisted scientific creation of Stan Lee and Steve Ditko, he wasSpider-Man’s greatest nemesis, wreaking havoc to fuel his own attempts of global domination and causing Spider-Man to go out of his way to protect the people he loved.

Which is why, in an epic showdown with Spider-Man that left both powerless, he sought the one option in sight – to swap brains with his nemesis.

Because of Peter’s residual memories,Doctor Octopusbegan to understand the responsibilities of a hero and gained a new perspective. He became the self-labeled hero, the Superior Spider-Man. Using his talents to aid rather than imperil, the doc’s stunning redemption in Amazing Spider-Man (Vol. 4) #25 was considered pretty iconic.

18The Punisher

A Cold-Blooded Killer

Introduced inAmazing Spider-Man #129in 1974 by Gerry Conway, Ross Andru, and John Romita Sr., Frank Castle was not always a hero. His creators had a different arc in mind, and for a while, the former soldier was driven to unbelievable extremes and organized crime. He used excessive lethal force when it was unnecessary, and even tried to kill Spider-Man and had a showdown with Daredevil at one point.

However, after facing defeat,The Punisherbegan to rethink his murderous crusade. He partnered up with the X-Man Nightcrawler to bring down Jigsaw and realized he could accomplish more if he cooperated with others. Castle joined secret wars, confronted Kingpin, helped the Power Pack defeat villains before eventually getting back with Spider-Man to defeat Hartmann, a neo-Nazi fanatic. Overall, The Punisher is one of the most complex antiheroes in the Marvel Universe.

Related:21 Strongest Marvel Comic Villains Who Haven’t Shown Up in the MCU (Yet)

17Mystique

Always a Flip-Flopper

A complete shape-shifter who calls herself “unchained and unleashed,”Mystiqueis one of Marvel’s longest standing villains. She first slithered like a shadow intoMs. Marvel #16as Raven Darkhölme, a mutant terrorist/consultant detective hired by Irene Adler. Created by Chris Claremont and Jim Mooney, Mystique was a hundred percent manipulative and cunning, no matter who she served.

16Sabretooth

Wolverine’s Nemesis

Created by writer Chris Claremont and artist John Byrne,Sabretoothmade his first appearance inIron Fist #14. Even as a child, Victor Creed had shown violent tendencies, and it did not help that he had the same inflicted upon him by his very own father. Growing up to be the ultimate Wolverine antagonist, Creed was a feral and ferocious fighter willing to murder and main anyone without showing the slightest bit of mercy.

However, after decades of seeing him at war with X-Force, fans were blessed with a new version of Sabretooth in alternate timelines. In the “Age of Apocalypse” storyline, he was showcased asa brave and devoted member of the X-Men.

In another storyline titled “AXIS,” Sabretooth was recruited by Magneto to help fight alongside him and Steve Rogers when Doctor Doom and Scarlet Witch cast an “inversion” spell that turned Marvel heroes into villains and vice versa. Following that, he turned himself in and became part of the Wolverines team.

A Member of the Guardians of the Galaxy

Venomwas the Friendly Neighborhood Spider-Man’s ultimate enemy. A not-so-friendly, dark, and destructive symbiote in black, he first took form in 1987’sAmazing Spider-Man #299.The symbiote’s history is unclear because of his modified memories, but fans know him as a broodier, menacing Eddie Brock.

Quickly becoming a fan-favorite Marvel character, Venom showcases value beyond destruction. So not only did he evolve from a bloodthirsty villain into an influential hero in the comics, but Venom also worked alongside the Avengers to face off against the oncoming onslaught of Knull, the King in Black, and teamed up with Peter’s former bully Flash Thompson and transformed into Agent Venom. Basically, Venom proves that there is hope in second chances.

14Red Hulk

General Ross Gets a Chance at Being the Hulk

A superhuman monster known to Marvel fans as a deadlier, more fearsome version of the original Hulk,Red Hulkrumbled with all his strength onto the screen inHulk (Vol. 2) #1. It was later revealed that Red Hulk was actually General “Thunderbolt” Ross (first appearing in the comics 1962’sIncredible Hulk #1). He was fused with gamma radiation, which gave him his volcanic rage.

Underneath the scarlet skin, Red Hulk possessed Ross’ soul – one where he had fought in the war and had a family. Like so many other characters, he also answered to missions alongside the Avengers, proving his wrath could help protect people as well. He formed bonds with Steve Rogers and Deadpool in their fight for justice.

13Swordsman

A Laughable Thunderbolt

This villain first surfaced inAvengers #19in 1964. Highly skilled in combat and a superb athlete,Swordsmanwas a mentor to young Clint Barton (and eventually Hawkeye). Throughout his arc in Marvel Comics, he oscillated between good and evil, while still committingvarious crimes across the worldand causing the Avengers much trouble.

He faked a message from Iron Man asking the Avengers to let Swordsman join the team, with a hidden agenda to infiltrate the gang and destroy it from within. However, when Swordsman was a part of the mighty heroes’ group, he developed close bonds with them and seemed to fit in so well that he felt guilty about placing bombs in the Avengers Mansion. In trying to diffuse them, he was caught by Captain America.

Related:15 R-Rated Marvel Comics That the MCU Should Adapt

12Silver Surfer

A Cosmic Presence

His motto was to “to fight to preserve that same opportunity – to love, to dream, to soar among the stars.” He was written by Stan Lee and created by Jack Kirby, heralding inFantastic Four #48. Call him Norrin Redd, Galactus’ Herald, orSilver Surfer, he was a favorite character among fans for a really long time. And his most stunning adventures were in Lee and Kirby’s “Galactus Trilogy.”

Serving an all-consuming master, Silver Surfer’s mission was to destroy worlds – including Earth. Yet when he arrived at the planet, Alicia Masters and The Fantastic Four convinced him that the Earth was a good place and the people on it were worth saving. He betrayed Galactus, became an outcast searching for redemption, and known across the universe as a powerful and devoted defender.

Magneto Was Right

This mutant icon first came into existence inX-Men #1in 1963. A Holocaust survivor,Magnetowas solely driven by his passion for survival of his kind, and he would go down darker paths and fight humans to protect the mutants. Across the decades shaping the X-verse, as Max Eisenhardt witnessed hate breeding more hate, he turned to carrying out more heroic acts.

He envisioned a future built on cooperation rather than conflict. So Magneto often teamed up with the X-Men to fight ruthless villains. He was also a significant part of the popular Marvel storyline where Professor X “supposedly” dies, and he honors Xavier’s memory by taking over the school as headmaster.