How Avengers: Endgame changed the Hulk-Bruce Banner dynamic could lead to a World War Hulk arc coming together in the MCU. Though the news hasn't been confirmed, a World War Hulk movie is rumored to be in development at Marvel. In the comics, “World War Hulk” was a Marvel Comics crossover event that saw Hulk and some of his allies wage war on his former friends and fellow superheroes on Earth.

The last time Hulk made a proper appearance in the MCU was in the beginning of Avengers: Infinity War when he was brutally beaten by Thanos (Josh Brolin) on Grandmaster’s ship. After refusing to emerge for the battle in Wakanda, Marvel made a shocking change to both Hulk and Bruce Banner by putting the latter’s consciousness in the Green Goliath’s body. The evolution into “Smart Hulk” served as the brand-new status quo for the two characters. By the end of Endgame, Banner was one of only three members of the original Avengers team to still have a presence in the MCU. So while the MCU is moving on from major heroes like Captain America and Iron Man, it’s still holding to Hawkeye (at least until his Disney+ series), Thor, and Bruce Banner. All three could be vital to future projects.

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Banner is confirmed to play a key role in Phase 4’s She-Hulk TV show, possibly as a mentor figure or as the character who sets Jennifer Walters’ transformation in motion. This means the MCU certainly does intend to lean on Banner, but what about the Hulk? As of now, it’s hard to say for sure what the studio will do with his other half (if anything). Avengers: Endgame seemingly closed the door on this chapter in Banner’s life by ending his struggle with the Hulk, but it could be that this was only the beginning to something much bigger.

Endgame's Hulk "Solution" Insulted The Jade Giant

Smart Hulk offering Scott his tacos in Avengers Endgame

Endgame’s “Smart Hulk” change was characterized as a “solution” to Banner’s problems in the movie and as a resolution to their story by the writers and the directors. The issue with this “solution” is that it was an insult to the Hulk’s character. That’s because this arrangement only favored Banner. It came at a great cost to the Hulk, but this was never acknowledged by the characters in the movie. No one seemed to recognize that Banner seizing control of Hulk’s body meant that the Hulk was essentially dead in the MCU. It’s important to keep in mind that on a fundamental level, Hulk and Bruce Banner are actually two different characters, which is why Endgame’s handling of their problem felt so flawed. It rewarded one personality with a key arc, while totally sidelining the other in a way that felt wholly unnecessary. This came as a huge disappointment to Hulk fans – and for good reason.

Shang-Chi Has Already Proved Banner's State Is Temporary

Bruce Banner in Endgame

Marvel made another notable adjustment to Banner in Shang-Chi and the Legend of the Ten Rings. In the movie’s mid-credits scene, Banner was among the heroes encountered by Shang-Chi (Simu Liu) and Katy (Awkwafina) at the Sanctum Sanctorum. Interestingly, he was shown to be human again, which proved that “Smart Hulk” was only a phase for the character. For a reason that might be explained in She-Hulk, Banner has somehow reclaimed his human form. Endgame’s Hulk twist not being a permanent change indicates that the door is open for more developments to take place with Banner and Hulk in the MCU.

Hulk Could Still Fight Back Against Banner And Cause A Disaster

Hulk prepares to leave at the end of Avengers Age of Ultron

Banner’s perspective on becoming “Smart Hulk” gave the impression that their merging was mutual, but of course, that’s only his side of the story. Given what’s known about the Hulk and the fact that his personality has been repressed for several years, it makes sense that he’d put up some resistance. For so long, he’s been caged in Banner’s mind, but that doesn’t mean he’s gone forever. Since it’s now become clear that the “Smart Hulk” state was just temporary, it’s possible that Hulk will fight back against Banner and regain control at some point in the future.

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Banner has made himself the dominant personality, but if he were to slip up and lose his temper, that could be the opportunity the Hulk needs to retake the driver’s seat. Hulk’s return would obviously be welcomed by fans, but it may not be a happy one for him or his allies. Being contained for so long against his will could turn him into a bigger threat than he ever was before. A disaster of colossal proportions could ensue if and when Hulk is finally unleashed.

How World War Hulk Could Work In The MCU

World War Hulk Doctor Strange Hands Smash

A rampage by the Hulk could result in the same circumstances that unfolded in “World War Hulk”. In the comics, the Illuminati (a secret collection of Marvel heroes who made behind-the-scenes decisions about the world’s safety) formulated a plan to send Hulk into space. They thought it was the best course of action, but it didn’t turn out that way at all. Hulk, furious at what had been done to him by people that he thought were his friends, made new allies in space and came back for revenge. Upon his return, he hunted down those he held responsible, including Doctor Strange, Mr. Fantastic, and Iron Man. It’s possible that the MCU’s heroes would develop a similar strategy to deal with the Hulk if he were to turn hostile in the MCU. If so, Marvel would have a blueprint for a World War Hulk story in a Phase 5 crossover movie.

Alternatively, Marvel could lead into “World War Hulk” with the setup it already has. There may not be a need for Hulk to be shot into space for his crusade to kick off since Avengers: Endgame already gave him plenty of motivation to go on a rampage. If Hulk emerges once again, he’s unlikely to overlook his teammates’ inaction in regards to his situation. Similar to his comic counterpart’s opinion that Doctor Strange and the others had betrayed him with their plan, the MCU’s Hulk would have every reason to think that the Avengers abandoned him. After all, none directly opposed Banner’s decision. Anger over this could result in a reckoning against all those who allowed this to happen.

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