Civil War, by writer Mark Millar and artist Steve McNiven, is one of the biggest Marvel stories of the 21st century. Pitting Iron Man and Captain America against each other in an ideological battle, it would change the Marvel Universe for years to come in its aftermath, completely recreating the landscape of the heroes and villains. Few 21st century event stories have had the impact of Civil War.

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The story had its ups and downs but it's impossible to deny just how important it was to the overall fabric of the Marvel Universe for years to come, its ending promising huge consequences for everyone.

8 The Creation Of The Thor Clone Destroyed Thor's And Iron Man's Relationship For Years

Thor's cyborg clone, Ragnarok, from Civil War.

Iron Man's side did a lot of pretty underhanded things during Civil War but the creation of the Thor clone almost took the cake. Part clone and part cyborg, the Thor clone made a splash right away, killing Goliath and mopping up members of Cap's Secret Avengers like they were nothing. The clone would be dispatched by Hercules at the end of the story and not be seen again for years.

Thor wasn't around when all of this happened but when he came back and found out what had been done, especially in his name, he was beyond angry. He attacked Iron Man and then ignored the Armored Avenger afterwards. They would fight side by side during Secret Invasion but wouldn't actually be friends again until after the Siege of Asgard.

7 Wolverine Would Become A Full Time Avenger

new-avengers-wolverine

Before Civil War, Wolverine joined the New Avengers, but he wasn't always around. Because of their reduced numbers and the fact that the government now had records on them, the X-Men weren't a part of the Registration battle and Cyclops had all of them stay out of it as much as possible. After Civil War, Wolverine would throw himself into the fight against Iron Man, going on the run with Luke Cage's New Avengers.

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Wolverine would start spending most of his time with the Avengers, helping them in battle against Iron Man's forces. He proved that he fit in well as an Avenger during this time and he would get embroiled in hunting down Skrulls and almost kill the Skrull Queen during the final battle of Secret Invasion.

6 Spider-Man Revealing His Identity Would Lead to One More Day

Spider-Man was forced to choose - and then abruptly change - sides during Marvel's Civil War event.

Because of Civil War, Spider-Man would lose one of the most important parts of his life. It all started with Iron Man talking him into revealing his identity on national TV. After the death of Bill Foster and Iron Man starting to bring villains into the fight, Spider-Man jumped sides to Cap's Secret Avengers, and Kingpin would target his family, with Aunt May taking a bullet.

All of this would lead to One More Day, where Spider-Man worked feverishly to find a way to save Aunt May. It would all be futile, though, and eventually his only recourse was to trade his marriage to Mephisto, who saved Aunt May and made everyone forget his secret identity. This would change Spider-Man and his life forever.

5 Speedball Would Become Penance

Speedball Penance

The catalyst for Civil War was a battle between a group of villains and the New Warriors, which would end in Nitro killing all of them but himself and Speedball, as well as hundreds of children. Speedball's survival would lead to a change in his powers, as it would now take pain in order for his kinetic energy powers to work again. He had special armor made for himself, with a spike for every child that died to fuel his powers.

Speedball became Penance, a much darker hero than he had been before. He ended up joining the Thunderbolts but disappeared from the team after Norman Osborn was named head of the Superhero Initiative after the battle against the Skrull in Secret Invasion.

4 The Avengers Would Split Into Two Teams

Mighty Avengers and New Avengers

After Iron Man became head of S.H.I.E.L.D., he would have to start over again with the Avengers, as most of the team's former members were all anti-Registration and underground. Turning to the heroes on his side, he brought together old hands like Ms. Marvel, Wasp, Wonder Man, and Black Widow with new blood like Ares and Sentry to create the Mighty Avengers, who would battle against a new Ultron and Doctor Doom while completely ignoring the Skrull threat.

Luke Cage and the remaining New Avengers would take refuge in Doctor Strange's house and work against Iron Man's side, revealing the Skrull infiltration and trying to figure out what was going on while staying one step ahead of Iron Man and his Avengers, who felt it more important to hunt them down than deal with real problems.

3 Norman Osborn Would Be Put In Charge Of The Thunderbolts

Norman Osborn and his Thunderbolts

Iron Man needed help against Cap's forces, so he he got help from a different place - the villains. Restarting the Thunderbolts Initiative, Iron Man also ended up freeing one of the most dangerous villains in the Marvel Universe, Norman Osborn. During Civil War, he stayed behind the scenes and worked against the forces of Atlantis, keeping them out of the war as much as possible.

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After things had settled down, Iron Man rewarded his loyalty by putting him in charge of the new Thunderbolts. Osborn commanded one of the most powerful Thunderbolts teams ever and threw his lot in with the heroes during the Skrull Invasion, which saw him gain even more power after he killed the Skrull Queen on national TV.

2 Captain America Was Taken Into Custody And Killed

The Death Of Captain America

Captain America had the whole thing won. His team had just broken free all of the heroes held in Iron Man's Negative Zone prison, evening up the odds and winning the resulting battle after Cloak brought them back to New York. Cap was about to take out Iron Man when a bunch of citizens stopped him, and he saw just how much damage the battle had done to the city.

Cap surrendered and was taken into custody. Unfortunately for him, this made him easy pickings for Red Skull, who had Doctor Faustus brainwash Sharon Carter into shooting him on the steps of the courthouse before he went to trial for his crimes during Civil War.

1 Iron Man Became Director Of S.H.I.E.L.D. And Botched It Completely

Iron Man Director of SHIELD in Marvel Comics

Iron Man was basically the bad guy of Civil War, going full fascist and leading the pro-Registration forces. It didn't matter what he had to do, Iron Man was going to win and he left a trail of shattered friendships and bodies in his wake. His reward for all of this shadiness was to be made director of S.H.I.E.L.D., which would usually be a good place for someone as untrustworthy as he is.

Iron Man was a terrible director of S.H.I.E.L.D., though. He missed the Skrull Invasion that was happening right under his nose, allowed Norman Osborn too much power, and was more concerned about hunting his old friends down than doing the job. Unfortunately, his failures allowed the Skrull Invasion to almost succeed and resulted in Norman Osborn's Dark Reign.

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