WARNING: The following article contains spoilers for Avengers: Endgame.

The character of Hulk has gone through quite an evolution in his time in the MCU. The complex relationship between Bruce Banner and  Hulk has seen many changes with each new appearance of the character, all culminating in one of the stranger developments in Avengers: Endgame. When we meet back up with the characters after the film’s five-year time jump, Banner and Hulk have come to some sort of understanding. They now coexist as one personality, taking the best elements of each; Banner’s mind and Hulk’s body.

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While this new version of Hulk might be surprising to some, comic book fans will recognize it as Professor Hulk. This character has been a fan-favorite for years, and while the movie has a lot of fun bringing him to the big screen, there’s a lot they leave out. Here’s everything you need to know about Professor Hulk.

10 10. Appearance

At a quick glance, Professor Hulk might appear to be quite similar to the classic look of the character, but he does actually have quite a distinct look. Due to a more harmonious existence with Banner, some characteristics of the latter begin to come through. As you see in the movie, while he remains his massive green self, Professor Hulk's face now more closely resembles Banner's than it ever did before.

Without the mindless rampaging Professor Hulk also gets to keep some clothes on his back. In Endgame, this seems to be an aspect he's particularly pleased about, even getting to don those fancy Quantum Realm outfits like the rest of the team.

9 9. The Different Personalities Of Hulk

An obvious question regarding Professor Hulk is how he came to be in the first place. In order to understand that, you need to understand the different personalities of Hulk. While some might assume it is just Banner and Hulk who share this body, there is also Grey Hulk.

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Grey Hulk goes back to the character's first appearance when Hulk was presented as grey before it was changed to resolve coloring issues. Marvel later made that version of the Hulk canon as a third personality who, like the others, is constantly fighting for control of their shared mind.

8 8. A New Personality

In the comics, Professor Hulk was born out of desperation when the fighting between all the Hulk personalities became too much for Banner to take. In an effort to solve the problem, Banner enlisted the help of Doc Samson, his friend and a genius psychiatrist.

Through Samson's work with Banner, they find a way to merge all the personalities of Hulk into one. This new merged personality is meant to end the split personality disorder Banner struggles with so he can live as one totally new personality, Professor Hulk.

While the origin of how Banner became Hulk is well-known to most fans, many probably are not familiar with his very tragic past. As a child, Banner's own father was a very abusive man and would later kill his wife and Banner's mother.

Through Samson's psychiatric intervening, he discovers that this might traumatic event might be contributing to the split personalities of Bruce's mind and the aggression between them. Professor Hulk is established as a way of bringing Banner some peace in regard to his past.

6 6. The Safeguard

Hulk in Thor: Ragnarok

Banner is often seen in the comics as being afraid or resentful towards the savage Hulk persona. He sees the rage of Hulk as too much of a liability and something he actively tries to oppress. While Professor Hulk is meant to be a way of dealing with the personality problems, Banner is still weary of that rage.

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To help ensure the savage persona of the Hulk does not take over, Banner help create a safeguard. This helps keeps Professor Hulk's rage in check so as not to allow the more dangerous side of their mind to take over.

5 5. Limited Strength

Hulk vs Modok Adamantium

As much as Banner may resist Hulk's rage, it is the thing that makes him the superhero he has the potential to be. The strength of Hulk is all tied to that rage. The more angry Hulk becomes, the stronger he becomes with no limit to how powerful he can be.

Due to Banner's precautions and the fact that his mind is in control, Professor Hulk does not have access to that limitless strength. By putting a limit on his rage, Professor Hulk is actually significantly less powerful than the normal Hulk.

4 4. Reverse Professor

As much as Professor Hulk might help to deal with a lot of the issues faced by Banner and Hulk, there are a few downsides to him as well. The fact that he has a cap on his strength is definitely a disadvantage, no longer allowing him to be the unstoppable force he usually is. But the real problem comes with Banner's safeguard.

If Professor Hulk does indeed risk raging into a savage mode, the safeguard kicks in and reverts him back to Banner's regular human body, but with the mind of Hulk. Needless to say, this is the worst of both worlds and the opposite of what Professor Hulk was supposed to achieve.

3 3. Armed And Dangerous

Red Hulk holding a smoking gun

Endgame's version of Professor Hulk doesn’t seem to have the kind of limitations on his strength as his comic book counterpart. Even after getting severely injured from using the Infinity Gauntlet, Hulk is still right in the middle of the massive battle. In the comics, Professor Hulk just isn’t the same fighter he once was.

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While Banner chose to sacrifice some of the brawn for brains, Hulk being Hulk, he still needs to be intimidating. Therefore, in some of his appearance, Professor Hulk goes into battle wielding massive guns to make up for his strength.

2 2. Redefined Hulk

Professor Hulk was a character change that came decades after the character had been establish as one of Marvel's most popular characters. But even after all those years and countless storylines, the creation of Professor Hulk helped introduce new elements to the character and change the way we perceive him.

Hulk was initially created to be a Dr. Jekyll and Mr. Hyde character with Bruce Banner's exposure to gamma radiation creating this new monstrous personality. Professor Hulk introduced the idea that Hulk was always a part of Banner's psyche and the gamma accident just unleashed him.

avengers-endgame-bruce-banner-hulk

In Avengers: Endgame, we see Banner as Professor Hulk seemingly content with his new existence which is not something we usually see from the character. Banner has always sought to keep Hulk at bay and searches for a cure for his condition. As Professor Hulk teaches him, this is actually what he wanted all along.

For Banner, Professor Hulk is the ideal version of himself. He gets to keep the strength without all the rage and mindless destruction. He finally sees that positives of having Hulk be a part of him and comes to terms with their relationship.

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