In Avengers: Endgame, Mark Ruffalo portrayed an intelligent Hulk who combined the Marvel hero's strength with the brains and warmth of Bruce Banner. However, that film almost featured a very different take on the Jade Giant.

In an interview with Backstory Magazine, Avengers: Endgame co-writer Christopher Markus confirmed that the Red Hulk was briefly supposed to appear in the film. However, it's not exactly clear what role he would have had or how different it might've been from the Red Hulk's role in the comic book Marvel Universe.

Between that ill-fated appearance and his nixed role in Captain America: Civil War, the Red Hulk could very well appear in future Marvel Cinematic Universe productions. Now, we're taking a look at who the Red Hulk is, what could've been and what the future could still hold for the super-strong Avenger.

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Who Is the Red Hulk?

The Red Hulk first appeared in 2008's Hulk #1 by Jeph Loeb and Ed McGuinness. While he still has Hulk-level super-strength, the Red Hulk's true identity was a mystery that fueled years of stories. In addition to his crimson hue, he was different from the Hulk in many ways. For one, he retained his intelligence, combining tactical cunning with brute strength, which stood in sharp contrast to the then-dumb green Hulk.

Whereas Hulk grows stronger as he gets angrier, Red Hulk instead emitted flames and could also absorb energy, from gamma rays to cosmic power. Red Hulk used this to force Hulk to revert to Bruce Banner and effortlessly take out powerhouse villains like the Abomination.

Eventually, the Red Hulk was revealed to be General Thaddeus "Thunderbolt" Ross, the archenemy and father-in-law of Bruce Banner. He was given his powers through a combination of gamma and cosmic rays by the Intelligencia and A.I.M. and sought to use them to better defend against the Hulk.

After the story that introduced him, Red Hulk became a somewhat uneasy ally to Marvel's heroes. He briefly joined the Avengers and organized a new incarnation of the antiheroic Thunderbolts.

How the MCU's Red Hulk Could've Been

Professor Hulk Avengers Endgame feature

While the Russo brothers' Civil War plans for Hulk seemed to center on Thunderbolt Ross, Markus implies that Endgame's Red Hulk would have simply been Bruce Banner by stating that "really we're just saying he changes color." Instead, the MCU's Hulk's changes into his "Professor Hulk" persona, which combines the Hulk's strength and body with Banner's intelligence and was introduced during Peter David's iconic tenure on Incredible Hulk.

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This still has shades of the Red Hulk, who has both intelligence and the ability to transform at will in comics. Considering how that transformation happened off-screen, it stands to reason that the Hulk's transition from green to red would've happened off-screen too, and it likely would've drawn the same criticism that unseen development did.

Who Will Be the Red Hulk?

William Hurt as General Thunderbolt Ross in a dark gray room in Captain America: Civil War.

As it stands, the Marvel Cinematic Universe already includes Thunderbolt Ross, as portrayed by veteran actor William Hurt. While he's played largely supporting roles since he was introduced in 2008's The Incredible Hulk, he could still theoretically become the Red Hulk.

While that could pave the way for a comics-accurate Red Hulk, Hurt is 69 years old, and he may not be in the market for an action role that would likely involve several sequel appearances. Still, the Red Hulk would almost certainly be created through the kind of motion capture technology that's been used to transform Ruffalo into the Hulk and Josh Brolin into Thanos, which keeps the idea of Hurt's Ross becoming the Hulk somewhat viable.

Assuming that Bruce Banner doesn't simply turn red, The MCU could also throw a curve ball and use General Robert L. Maverick, Marvel's second Red Hulk. Created by Al Ewing and Gerardo Sandoval in the 2017 series U.S. Avengers, the general transformed at will using a wrist-mounted device. He also keeps his intellect when transformed, but can only remain as Red Hulk for an hour. Using this version of the character would allow Marvel to find a new face for the human side of the Red Hulk and offer a cleaner slate to build up the character as needed.

Where Could Red Hulk Appear?

Red Hulk Thunderbolts

As with the incredible Hulk himself, Red Hulk's most likely appearance would be in the upcoming She-Hulk Disney+ series. Even with a Disney+ budget, it's not clear how many gamma-irradiated heroes the show could feature before becoming outrageously expensive. Since the show was only just announced, it's also not clear when it might premiere or if it would be part of Marvel's Phase 4 or Phase 5.

With no new Avengers movie in the foreseeable future, it's not totally clear where the Red Hulk could appear on the big screen either. While a Young Avengers series is reported to be in the works for Disney+, the scope of this show will most likely be hamstrung by virtue of it being a streaming show, and Red Hulk doesn't have a strong connection to those characters.

The Red Hulk would make the most sense as a member of a potential movie about the Thunderbolts or the Dark Avengers, which would likely feature reformed villains or dark mirrors of former Avengers. Since Ant-Man and the Wasp featured Ghost, and U.S. Agent will appear in The Falcon and The Winter Soldier, Marvel may already be setting the team up as its answer to the DCEU's Suicide Squad. Whether its in one of these productions or elsewhere, it's probably only a matter of time until Red Hulk smashes his way onto the big screen.

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