In comics, first appearances mean something. While the debut of a major character can become a valuable collector's item, a first appearance can be a chance to get in on the ground floor of a hero who might survive for generations. While a character might go on to star in thousands of comics, shows and movies, each character only has one first appearance, and that carries a symbolic importance. That debut usually casts a long shadow that defines the character in the minds of comic readers and creators. Over time, every character will evolve and change to some extent, but some characters almost transform into completely different creations. While those kinds of changes can happen with any publisher's characters, it seems to happen quite frequently with the heroes of Marvel Comics.

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Now, CBR is counting down some Marvel heroes who are completely unrecognizable from how they appeared or acted when they debuted. For this hardly comprehensive list, we'll be looking at characters whose appearances, allegiances, abilities and roles within the Marvel Universe changed drastically over the years. While some of these changes were mandated by passing trends, others revealed hidden depths that may have even been unknown to a character's creators.

15 BEAST

Beast immonen

When Stan Lee and Jack Kirby created Beast in 1963's X-Men #1, Hank McCoy was a teenage genius with extra large hands and feet. While his enhanced dexterity and agility briefly gave him success as a high school sports star, the young mutant found a home at Xavier's School for Gifted Youngsters, where he became one of the founding X-Men.

In 1972's Amazing Adventures #11, by Gerry Conway and Tom Sutton, Beast took an experimental serum that gave him his famous gray, then blue fur and an apelike appearance. This was the cheery character's signature look until a wave of "secondary mutations" hit Marvel's mutants in 2001. Thanks to the power-activating X-Man Sage, Beast transformed into a more feline creature with less dexterity but greater strength and speed. In 2013, his younger self time-traveled to the present day and helped the elder, more tortured McCoy regain his famous simian appearance.

14 CABLE

Nathan Summers Cable

While Josh Brolin might be bringing Cable to life in 2018's Deadpool 2, Nathan Summers was a baby in a bubble. When he was created by Chris Claremont and Rick Leonardi in 1986's Uncanny X-Men #201, Nathan was merely the newborn son of Cyclops and Madelyne Pryor, Jean Grey's clone. After Pryor went evil and led a demonic invasion of New York, Cyclops and Jean raised Nathan, and the young mutant usually formed a telekinetic bubble to protect himself during his parents' adventures.

When Apocalypse infected him with a techno-organic virus in 1991, Nathan was sent into the far-future for treatment. Back in 1990's New Mutants #86, Rob Liefeld and Louise Simonson introduced Cable, a mysterious gray-haired telepathic soldier from the future with a metal arm. After some vague hints, the two concepts were connected, and Cable was confirmed to be the adult Nathan Summers, ravaged by a lifetime of war.

13 STAR-LORD

Star-Lord First and Modern

Long before Chris Pratt brought Star-Lord to life as the leader of the Guardians of the Galaxy, Peter Quill made his debut in 1976's Marvel Preview #4, one of Marvel's black-and-white magazines aimed at older readers. Created by Steve Englehart and Steve Gan, Star-Lord was an unpleasant, arrogant NASA astronaut who became an intergalactic policeman, the Star-Lord.

After making a few appearances over the years, Star-Lord was introduced to the main Marvel Universe in 2004, shortly before he played a major role in the cosmic 2006 crossover Annihilation. Even though this prepared the character for his cinematic debut, these appearances didn't really fit in with his earliest adventures. Subsequently, all of the original Star-Lord's adventures were rewritten to have taken place in an alternate universe, Earth-791. After Chris Pratt defined Star-Lord in the Marvel Cinematic Universe, Marvel's main comics Star-Lord took on some of his snarky irreverence.

12 GROOT

First and Modern Groot

For most audiences, Groot is defined by his gentle nature and his trademark words, "I am Groot." While those qualities have shaped the tree-like alien both in comics and on film, that hasn't always been the case. When the original Groot was created by Stan Lee and Jack Kirby in 1960's Tales to Astonish #13, he tried to conquer Earth and gave several villainous monologues before he was defeated by termites.

When Groot made his debut and joined the Guardians of the Galaxy in 2007's Annihilation Conquest: Star-Lord #1, by Keith Giffen and Timothy Green II, he still spoke and acted like a supervillain. After sacrificing himself for the team, Groot regrew from a sapling, but had considerably weaker vocal skills. After his vocabulary dwindled to "I am Groot," this Groot was given a new backstory that dropped his ill-fated invasion of Earth.

11 FLASH THOMPSON

Flash Thompson Then and Now

As the history of the Marvel Universe has unfolded, Spider-Man's friends and allies have slowly grown up with him. One of Peter Parker's most complex friends is Flash Thompson. When he was created by Stan Lee and Steve Ditko in 1962's Amazing Fantasy #15, he was Parker's bully in high school. After he and Parker became friends in college, Thompson served a few tours of duty in the U.S. Army, where he sustained injuries that required the amputation of both legs below the knee.

In order to replace his legs, Thompson accepted an offer to bond with the Venom symbiote for the U.S. government. As Agent Venom, Flash fought personal demons as he struggled to control the monstrous symbiote, battled actual demons, joined the Secret Avengers and eventually became the Avengers' representative on the Guardians of the Galaxy. More recently, Thompson returned to Earth and was separated from the symbiote.

10 BLACK WIDOW

Black Widow Then and Now

When Stan Lee, Don Rico and Don Heck created Black Widow at the height of the Cold War, she was a villainous Russian spy. In 1964's Tales of Suspense #52, Natasha Romanov infiltrated Stark Industries as part of a plot to assassinate a Soviet scientist who had defected. Instead of her sleek catsuit, she wore an elaborate costume that combined gaudy formal wear with web-like fishnets. When she tried to turn Hawkeye against Iron Man, she wore an even more elaborate fishnet-based uniform that seemed equally unsuited to covert activities.

Thanks in part due to her love for Hawkeye, Black Widow defected too, and became an occasional supporting character or antagonist to the team. In 1970, she traded in her flashier costumes for the sleek bodysuit that's become her signature look. Black Widow joined heroic organizations like S.H.I.E.L.D., the Champions and the Avengers, where she's been a member and team leader.

9 NICK FURY

Nick Fury Then and Now

Even though Nick Fury is Marvel's most famous spy, he originally began as a two-eyed World War II-era soldier. Created by Stan Lee and Jack Kirby in 1963's Sgt. Fury and the Howling Commandos #1, Sgt. Fury led an elite team that fought alongside Captain America during the war. As later stories revealed, Fury lost eyesight in his left eye due to a shrapnel injury and began working for the C.I.A. after the war.

In 1965, Lee and Kirby recast their wartime hero as Nick Fury, Agent of S.H.I.E.L.D. After starring in his own espionage-filled adventures, Fury became a fixture around the Marvel Universe as the director of S.H.I.E.L.D. In the 2013 crossover, Original Sin, Fury revealed that had committed various interstellar crimes to protect the Earth and fought Marvel's heroes. The now-elderly Fury became Earth's new Watcher, while his previously unseen son, Nick Fury Jr., joined S.H.I.E.L.D.

8 MAGIK

Magik Then and Now

While several iconic X-Men had memorable introductions in Len Wein and Dave Cockrum's Giant-Size X-Men #1, Magik wasn't one of them. In that 1975 issue, the young Illyana Rasputin had no dialogue and was only there to be saved by her brother, Colossus. After a few years as a minor background character, Illyana was transported to Limbo, where she grew several years older, became a sorceress, manifested teleportation powers, and took over the hellish dimension.

After taking the name Magik and returning to Earth, she garnered a starring role in New Mutants. After thwarting a demonic invasion of New York in 1989's "Inferno" crossover, she was de-aged back into adolescence and contracted the Legacy Virus, a mutant plague. Since her subsequent resurrection, the now-adult Magik has worked with the X-Men while trying to keep the darker aspects of herself at bay.

7 JUBILEE

Jubilee Then and Now

Even though she wasn't the X-Men's first teenage sidekick, Jubilee is one of Marvel's most famous young mutants thanks to her prominence throughout the 1990s. When she was created by Chris Claremont and Marc Silvestri in 1989's Uncanny X-Men #244, Jubilation Lee was a mallrat with the ability to shoot fireworks from her fingers. After befriending Wolverine, she joined the X-Men and the young mutant team Generation X.

Like most of Marvel's mutants, Jubilee lost her powers during the 2005 storyline House of M. After a brief stint as the technology-based hero Wondra, Jubilee was exposed to a virus that turned her into a vampire. Over the next few years, she struggled to adapt to her newfound bloodlust and adopted an orphaned baby named Shogo. Since returning to the X-Men, Jubilee has started teaching a new generation of mutants about how to deal with their powers in Generation X.

6 JANE FOSTER/THOR

Jane Foster Then and Now

Even though she plays the central role in Marvel's ongoing The Mighty Thor, Jane Foster used to go years between appearances. When she was created by Stan Lee and Jack Kirby in 1962's Journey Into Mystery #84, Jane Foster was a nurse who assisted Dr. Donald Blake, Thor's frail human guise. While Jane and Thor had a brief relationship, Odin broke them up and wiped her memory of their time together. Despite that, she became a doctor and made the occasional appearance in Thor's periphery over the following decades.

After Thor Odinson was deemed unworthy to wield his hammer, Jane picked Mjolnir up and became the new Thor in the aftermath of 2013's Original Sin crossover. Since then, she's served as the Asgardian Goddess of Thunder, an Avenger and has been one of the most important, visible heroes in the Marvel Universe.

5 ANGEL/ARCHANGEL

Angel Now and Then

Like many other X-Men, the once-carefree Angel underwent a famous transformation that unleashed a savage beast inside him. As one of the original X-Men introduced in Stan Lee and Jack Kirby's X-Men #1, Warren Worthington III grew up spoiled from a life of wealth and privilege. After a brief stint as a solo costumed vigilante, the young mutant joined the X-Men to learn how to better control his massive feather wings.

After a lifetime of adventures, Angel's wings were mutilated and amputated. In order to replace his wings, Angel joined Apocalypse, who gave him deadly new metal wings and turned him into the savage, blue-skinned Archangel. While Archangel eventually returned to his old team, he never quite got over his time as Apocalypse's Horseman of Death. As he's vacillated between Angel and Archangel, Warren has struggled to reconcile the two distinct sides of his personality over the subsequent years.

4 SONGBIRD

Songbird Now and Then

Before she joined the Thunderbolts and became a New Avenger, Songbird was a pretty unremarkable supervillain. Originally called Screaming Mimi, Melissa Gould was created by Mark Gruenwald, Ralph Macchio and John Byrne in 1974's Marvel Two-In-One #54. With a supersonic scream, Gould was a member of the Grapplers, a team of wrestlers-turned-supervillains, made a handful of appearances and later joined the Masters of Evil.

While the Avengers were trapped in an alternate dimension in 1997, the Masters of Evil posed as a new heroic team, the Thunderbolts. Screaming Mimi became Songbird, and her sonic scream morphed into a several sound-based powers including the ability to form "solid sound" constructs. Like most of her teammates, Songbird genuinely reformed and became a hero. Although she's never been away from the Thunderbolts for too long, she served with one team of New Avengers and was a warden at the Raft, a supervillain prison.

3 PSYLOCKE

Psylocke Then and Now

When Chris Claremont and Herb Trimpe created Betsy Braddock in 1976's Captain Britain #8, the telepathic mutant and model was a minor character in the ongoing adventures of her brother, Captain Britain. Shortly after her American debut in 1986's New Mutants Annual #2, she joined the X-Men and took the name Psylocke.

After a few years with the X-Men, Psylocke changed forever in a controversial story with a complex legacy. In a 1989 storyline by Chris Claremont, Marc Silvestri and Jim Lee, Psylocke's mind was essentially swapped with the mind of a comatose Japanese ninja named Kwannon. In her new body, Psylocke gained superior martial arts skills, a more aggressive personality and her trademark ability to focus her telepathic energy into a psychic blade. After a brief stint as a mind-controlled villain, Psylocke returned to the X-Men and has led a few different X-teams over the past few years.

2 PATSY WALKER/HELLCAT

Patsy Walker Then and Now

Although she eventually became a superhero and an Avenger, Patsy Walker was originally meant to be Marvel's answer to comics like Archie. Created by Otto Binder and Ruth Atkinson in 1944's Miss America Magazine #2, Walker was just an ordinary girl who navigated the perils of teenage and young adult life in those early comics.

In 1972, Steve Englehart and Tom Sutton brought her firmly into the superhero side of the Marvel Universe as one of Beast's friends in Amazing Adventures #11. A few years later, she became the costumed hero Hellcat and used her costume-enhanced abilities to save the Avengers. During her superhero career, Hellcat served with the Avengers and the Defenders before an ill-fated marriage with Daimon Hellstrom. While Hellcat never found another long-term home, she starred in several tonally divergent miniseries, including the recently-concluded Patsy Walker A.K.A. Hellcat!

1 BUCKY/WINTER SOLDIER

Bucky Winter Soldier

For decades, one of comics' unspoken rules was that Bucky stays dead. Created by Joe Simon and Jack Kirby in 1941's Captain America Comics #1, the young James "Bucky" Barnes was Captain America's plucky sidekick during World War II. While Bucky's death at the hands of Baron Zemo was his defining moment for years, later stories revealed that he was secretly a covert assassin during the war.

In Ed Brubaker and Steve Epting's essential 2005 Captain America story "Winter Soldier," Bucky came back. While Bucky still lost an arm and his memories, it was revealed that the Soviets had rescued Bucky and turned him into a cryogenically-preserved assassin, the Winter Soldier. With his handy cybernetic arm, Bucky battled his old mentor until he remembered who he was. Since then, Bucky has been Captain America, an Avenger and a major player in the ongoing sagas of the Marvel Universe.

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