Iron Man is definitely one of the most important characters in all of Marvel Comics. He was one of the founding members of the Avengers and his genius inventions have helped save the world plenty of times. In 2008, Iron Man's film was hugely popular and its success helped to build the rest of the Marvel cinematic universe.

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Tony Stark is has become a fan favorite character both in the comic books and on the big screen. However, Stark has not always been the heroic figure that Marvel fans have come to know and love. Here are the 10 biggest mistakes Iron Man has ever made.

10 Weapons Of Mass Destruction

Tony Stark is often portrayed as an abundantly wealthy businessman, but his wealth has some dark origins. The Stark family business has deep roots in weapon manufacturing. Tony Stark himself began using his genius intellect to create extremely deadly missiles, selling them to the highest-paying customers.

In the MCU, Tony Stark's origin story is directly tied to the complications of making weapons. When he sees the damage his tech is doing around the world, Stark decides to never pursue weapon manufacturing again and instead shifts his innovating towards making incredibly powerful suits.

9 Tries To Make Banner Angry

The Avengers Bruce Banner Tony Stark

As a scientist himself, Stark had a mutual admiration and respect for Bruce Banner. The two characters have worked really well together, brainstorming and coming up with new inventions together. However, one of Tony's biggest mistakes was when he attempted to provoke Banner when the Avengers are going up against Loki in the MCU.

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Stark tries making Banner angry in a jovial way, but the consequences would have been catastrophic if he had succeeded. The entire team of heroes would have been trapped in a plane thousands of feet in the air, trying to stop the Hulk before he brings the plane down.

8 Demon In A Bottle

Tony Stark looking drunk and confused in the cover of Demon in a Bottle

This iconic Iron Man story details Stark's battle against himself and his addictions. Tony Stark has had a problem with alcohol for a while. In this run, Iron Man drinks to forget the struggles that he has been through, attempting to escape his past. However, operating his incredibly powerful suit while under the influence is one of the biggest mistakes Stark has made.

Iron Man's problems with alcohol have become an important part of the character. Even in the MCU, Tony Stark gets drunk at a party and puts on his suit to entertain his party guests. This struggle with drinking has consistently been a problem for Iron Man over the years.

7 Created Ultron

Ultron MCU

Ultron proved to be a formidable villain for the Avengers. While he was originally intended to save the world, his motivations took a dark turn when he became self-aware, turning on the team of superheroes. In the comics, Ultron was invented by the brilliant Hank Pym. However, in the MCU, Iron Man builds Ultron without discussing it with his fellow heroes.

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His plan ultimately backfires and the team must work together to stop one of Iron Man's biggest mistakes. Ultron immediately becomes self-aware and decides to eliminate the Avengers and replace humans with machines. Stark going behind the team's back while building Ultron proved to be one of his biggest mistakes.

6 Banished Hulk

World War Hulk World Breaker Hulk

Prior to the catastrophic events of World War Hulk, Tony Stark and his associates decide to banish the Hulk from Earth. After the ship leaves the planet, Hulk's pregnant wife is lost in a tragic spaceship explosion. Banner inevitably blames Iron Man for this tragedy and he returns to Earth to seek his revenge.

Because of the decision that Stark had made to banish the Hulk, destruction followed. Hulk led his fierce group of fighters to Earth where he went on a rampage to bring down Iron Man and his associates. Because of this mistake, Iron Man was responsible for a good deal of the damage that the Hulk caused.

5 Faked His Death

Iron-Man-2-War-Machine

The death of Iron Man has happened more than once, each time the hero manages to return in some way. In one particular storyline, Tony Stark fakes his own death only to return later on. The stunt was on purpose, Tony Stark planned the incident to appear as if he had died in order to come back later unexpectedly.

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The plan was effective, but Stark did not let his best friend Rhodes in on the plan. War Machine has been a true friend and partner to Iron Man, so for a brief time, Rhodes had to believe that his best friend was dead. Not letting Rhodes know about the plan ahead of time was not a great move from Iron Man.

4 Sokovia Accords

Sokovia Accords Captain America Civil War

In the MCU, Iron Man is haunted by the decisions he has made in the past that have led to the destruction around the world. While his intentions may have been good, Stark chooses to side with the Sokovia Accords against the will of Steve Rogers and many members of the team. The Accords would submit the team to a higher authority, where several countries would dictate where the team goes and what they do around the world.

This Accord proved to be a hindrance and a bad direction for the team. While the decision did not last, butting heads with Steve Rogers proved to be a considerable mistake by Iron Man that ultimately broke the team apart.

3 Extremis

Iron Man dons Extremis armor in Marvel Comics

Extremis was first introduced as a virus, where the infected person would slowly be replaced by a different more extreme version. In certain cases, the virus gave people enhanced attributes and made them more aggressive.

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Iron Man at one point gave everyone easy access to this drug and then raised the prices once people were addicted. Although he was under the sway of a villain, this proved to be one of the worst things Tony Stark had done. He got people addicted to his product and then took advantage of them to make a huge profit.

2 Prison 42

During the events of the Civil WarIron Man had a major part in crafting an extremely well-protected prison that was made for keeping superheroes captive. Along with Reed Richards, Tony Stark built this advanced prison in the negative zone, with portals all across the country to effectively secure and transfer superheroes with ease.

This prison was successful for a time in detaining some heroes against their will. This proves to be one of the biggest mistakes Iron Man has made, he held other heroes against their will because they disagreed with him.

1 Cloned Thor

Cloning the god of thunder will always be Iron Man's biggest mistake. This also took place during the events of the Civil War, when the conflict grew to the point where heroes started taking up arms against each other, Iron Man had the audacity to clone Thor in hopes of winning the battle. With the help of other geniuses like Reed Richards and Hank Pym, Tony Stark successfully cloned his former ally, but the plan backfired when the clone ended up being much more aggressive.

The cloned version of Thor lept into action, killing Goliath with a bolt of lightning. Iron Man's actions directly led to the death of a fellow hero, because of his arrogance and brashness. Fans have not forgotten this moment and it will forever be one of the biggest mistakes Iron Man has made.

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