One of the reasons we all love the MCU so much is how perfectly cast the major characters are. Of course with any superhero movie, fans are going to have opinions on who should play their favorite heroes and villains. However, a lot of the time they're wrong.

Just like with Michael Keaton, Heath Ledger, Anne Hathaway and Ben Affleck, fans jumped to the wrong conclusion about some of Marvel’s best. With that in mind, here are 10 MCU castings we were all wrong about.

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BRADLEY COOPER

The announcement that the Guardians of the Galaxy were heading to the big screen led to a lot of questions. Chief among them was how Rocket Racoon would work in a live-action film. When popular actor Bradley Cooper was chosen as the voice of Rocket, the doubts got even louder.

Audiences didn't see the heartthrob as the ideal pick for the foul-mouthed, sarcastic raccoon. Turns out they had nothing to worry about since Cooper has made Rocket one of the funniest and most popular characters in the entire MCU. Not only that, but his growth throughout the Guardians films and the last two Avengers movies show that there is a lot of heart behind his rough, furry exterior.

CHRIS PRATT

Star-Lord (Chris Pratt) HD - Guardians of the Galaxy

As Parks and Rec's lovable goofball Andy Dwyer, Chris Pratt showed off his comedy chops, but there wasn't much that screamed “superhero.” Fortunately for moviegoers director James Gunn felt differently.

Before Pratt got into Star-Lord shape he was heavily criticized for his weight. With Gunn's support, Pratt proved those people wrong and was praised for his performance that blended comedy and action in the unique Guardians way. He is now one of Hollywood's biggest stars and has three different blockbuster franchises under his belt.

BENEDICT CUMBERBATCH

Dr. Stephen Strange was a character audiences were not expecting to see on the big screen. When the studio announced he was joining the MCU, fans suggested everyone from Joaquin Phoenix to Matthew McConaughey become the Sorcerer Supreme.

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The casting of Sherlock star Benedict Cumberbatch was a surprise fans didn't see coming, and some had a negative reaction. The actor didn't need magic to change their minds, he simply made the character and origin story much more interesting than anticipated. In Cumberbatch's hands, Doctor Strange became a pivotal part in defeating Thanos.

MARK RUFFALO

Anytime a character is recast it causes controversy. In the case of Bruce Banner/The Hulk, things got even more heated as the disagreements between Marvel Studios and Edward Norton played out publicly. By the time The Avengers came around Mark Ruffalo had stepped into the role.

It's not like anyone was extra vocal against Ruffalo, it was just an adjustment for fans to get yet another Hulk after previous big screen attempts had failed. As one of Hollywood's most decorated actors, Ruffalo didn't miss a beat in bringing depth to both sides of his hero, making us love The Hulk and Bruce more than we ever had before.

TOM HOLLAND

Where do we begin with Peter Parker's feature film journey? As The Amazing Spider-Man 2 signaled Sony's inability to get another Spidey franchise off the ground, fans clamored for him to join the MCU. When the news came that it would actually happen, the audience was pretty vocal about their support for Andrew Garfield.

Ultimately, Marvel Studios wanted to start over and decided to cast Tom Holland. His charming debut in Captain America: Civil War perfectly captured Peter's enthusiasm for hero work and built an all new relationship between him and Tony Stark.

ZENDAYA

With the relaunch of Spider-Man came fresh versions of his friends and family. When former Disney Channel star Zendaya was cast, there were rumors she was playing Mary Jane, prompting a backlash against the actress from trolls who said she couldn't possibly be played by a woman of color.

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This harassment continued until her character was revealed to be named Michelle. Though, when she said she prefers MJ, these people lost their minds again. Spider-Man: Far From Home looks to continue her dynamic with Tom Holland that was largely only teased in Homecoming  and we have no doubt Zendaya will prove people wrong again.

TESSA THOMPSON

Thor Ragnarok was a reset for the character and movies. One of the new additions was Tessa Thompson as Valkyrie. Right on time came the internet grumblings that she was supposed have blond hair and blue eyes.

Thompson quieted the haters with a memorable performance as a weary, guilt-ridden warrior just trying to survive. She was so instantly popular that her absence in Infinity War was one of the film's few criticisms. Thankfully, her story in Endgame set up future MCU adventures and appearances.

IDRIS ELBA

Heimdall holding his sword and looking up in Thor: Ragnarok

Here's the thing about comic books, when most of them were created, the vast majority of characters were white. Now that it's 2019, we've seen more characters played by actors of color. Unfortunately, there will always be racist fans who site tradition as a reason to complain about certain castings.

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Idris Elba suffered this first hand when he was picked to play Heimdall. The internet was full of “he can't be an Asgardian God” comments. Elba shook them off and delivered his usual amazing performance, leading the same haters to lament his death in Infinity War and cheer his casting in The Suicide Squad.

CHRIS EVANS

Following the disappointment of Fantastic Four and its follow up Rise of the Silver Surfer, Chris Evans wasn't anyone's first choice to be Captain America. Even the actor had reservations about making such a big commitment and had to be convinced.

Thank goodness we were all wrong and got the Cap we'd been waiting a lifetime to see on the big screen. Turns out he was so perfect as Steve Rogers, he's become synonymous with Captain America. Cut to eight years later and while we're happy Cap got the life he deserved, we can't imagine what the MCU will be without Evans or Steve.

ROBERT DOWNEY JR.

robert-downey-jr-iron-man

There's no denying that without Robert Downey Jr. there would be no MCU. Launching the universe with Iron Man was a risky move, but casting Downey seemed even riskier in fans’ eyes. They couldn't see the actor as a billionaire, playboy, genius, philanthropist Tony Stark.

Twenty-two films and $20 billion dollars later, all those people were proven extremely wrong. It can't be said enough how important RDJ has been to Marvel, but we're sure his loss will become even more pronounced as the franchise he built from scraps in a cave continues without him.

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