Avengers: Endgame was a bittersweet film. Despite all the amazing moments it delivered, it meant we also had to say goodbye to the hero who started the MCU, Iron Man. Though he was not a popular character before his big-screen debut, the MCU and Robert Downey Jr. have helped make Tony Stark and Iron Man household names.

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The character had an amazing arc throughout the franchise, from selfish billionaire to a hero willing to sacrifice it all. And though he was just a man in a suit, he proved he could go toe-to-toe with just about any enemy around. Here are Iron Man's best fights in the MCU.

First Mission (Iron Man)

Iron Man walks away from an explosion

After learning what his weapons are being used for, Tony Stark realizes he can no longer sit back and do nothing as innocent people suffer. He decides it is time to use the suit that saved his life to go save other people's lives as well.

Flying to the Middle East, not far from where he was captured, Iron Man arrives in the besieged village and starts giving the terrorist soldiers a taste of their own medicine. This is the first time we see the actual Iron Man suit in action and it does not disappoint as he takes down the entire army.

House Party (Iron Man 3)

Legion of Suits in Iron Man 3

It became a joke in the MCU about how many versions of the Iron Man suit Tony has. He's always building and tinkering with his design that he seemed to have amassed an endless number of suits. Iron Man 3 decides to let us see all of them in action.

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After being without his suit for most of the film, Tony initiates the House Party protocol and his army of suits arrive to help take on the army of Extremis soldiers. The action sequence is fun and inventive as we see different styles of the suits kicking ass together.

Missing Pieces

Tony Stark aiming a gun in Iron Man 3

Iron Man 3 tries to switch things up with the story by forcing Tony Stark to try to survive without his armor. However, in one particular scene, Stark proved he can still be pretty badass even with just a few of his armor pieces.

While trapped in Killian's compound, Tony calls upon his suit but most of the pieces are delayed. So he proceeds to break out and fight his way through a squad of goons with one arm blaster and one boot. It's a lot of fun seeing him improvise in this chaotic and messy way that shows a grittier side to the Iron Man action.

Whiplash In The Race Track

Iron Man 2 didn't connect like the first film did and many people point to lackluster villains as a major problem with the sequel. While Mickey Rourke's Whiplash is certainly not all that compelling, he does get one great sequence.

As Tony arrogantly decides to race in the Grand Prix, Whiplash walks onto the race track and attacks using his electrified whips. The sequence is exciting and nerve-wracking, with its unique setting. The moment set Whiplash up to be a truly intimidating villain but never topped that moment.

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Meeting Thor

The Avengers stills/wallpapers

Part of the fun of the first Avengers movie was seeing so many iconic characters sharing the screen for the first time. Not surprisingly, given the egos at play with these characters, they don't all get along so well at first.

After Thor arrives and takes Loki, Iron Man takes issue and faces off with the God of Thunder. The scrap between the two is more fun than threatening but it is filled with great moments. From Thor headbutting Iron Man to the lightning recharging Iron Man's battery, it's a real crowd-pleasing moment.

New York Invasion

Iron Man's Mark VII In Avengers

With all the heroes gathered on a team together, they needed a pretty big threat to face off with. Loki's Chitahuri army did the trick as an endless number of them come pouring from a portal in the sky and begin attacking New York City.

The extended invasion sequence is one of the most fun action sequences in the MCU with all the heroes getting their moments to shine. Iron Man has some great highlights including pulling a "Jonah and the whale" maneuver on one of the Leviathans.

Escape From Captivity

Iron Man behind the scenes Mark I armor

Unlike most of the other heroes in the MCU, Stark's power comes from his mind rather than his muscles. Though he is physically an ordinary man, he was able to create something that made him extraordinary.

After being captured by the Ten Rings and forced to build weapons, Stark builds a suit of armor and enacts his escape. Seeing the first Iron Man emerge from the dark and start kicking all the terrorists' asses was a spectacular, cheer-worthy moment. Though the suits would get much more impressive, seeing the low-key suit do its thing was great fun.

Stand Against Thanos

Iron Man faces off against Thanos in Avengers: Infinity War

Very early in Avengers: Infinity War, Thanos proved there were few heroes that would be a match for him. While Iron Man might not seem as strong as Thor and Hulk, he showed he could give Thanos a pretty hard time one-on-one.

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With the other Avengers out, Iron Man battles the Mad Titan, trying desperately to keep him from getting the Time Stone. You can see the desperation in Stark's face as he throws everything, he has at Thanos and won't back down. While he doesn't win, he does manage to draw blood.

Hulkbuster

MCU Hulkbuster Versus Hulk Avengers Ultron

Hulk is maybe the most powerful Avenger, but also the most unpredictable. He is just as likely to fight one of his own teammates as he is the enemy. So it makes sense that Tony and Bruce Banner would take some extra precautions for those angry moments.

When Scarlet Witch casts a spell, Hulk loses control and begins rampaging. Tony calls in the Hulkbuster armor and the two square off. The brutal, fun and chaotic fight is a massive sequence that shows both these powerful heroes should not be messed with.

Fighting Captain America

Given how many enemies are out there, the Avengers sure spend a lot of time fighting each other. However, this particular battle is much more serious than a grudge match and it makes for one of the most personal and heartbreaking scenes in the MCU.

After learning Bucky killed his parents, Tony wants revenge but Captain America is standing in his way. After fighting alongside each other many times, these two heroes face off in a brutal fight where they are truly trying to hurt each other. It is a shocking fight that leaves more than just physical damage.

NEXT: 10 Times Iron Man Was The True Villain Of The MCU