Avengers 5 will be playing with a very different set of heroes - which new Marvel characters could it introduce? Avengers 4 is due in May 2019, and although it's the shortest wait yet between Avengers movies, it's perhaps the most excruciating, as fans are desperate to see how Cap, Iron Man and the remaining heroes can bring back billions of people from the dead and defeat Thanos once and for all. While it's a question of "how" rather than "if", fan debate is inevitably going to gently shift towards the inevitable Avengers 5, due at some point in the next five years.

Even though Avengers: Infinity War had one of the biggest ensemble casts in movie history, there remains an untapped wealth of characters for Marvel to choose from to populate its future Avengers roster, especially with the increasing likelihood of franchise mainstays Robert Downey, Jr., Chris Evans, et al soon stepping away from their iconic places in the pantheon. Some already exist as supporting characters in previous Marvel movies, with the capacity to go further and expand their roles; think Shuri stepping into the role of Black Panther, or Ant-Man's daughter Cassie Lang growing up to step into her father's gargantuan shoes as Stature.

Related: Predicting The Next 20 MCU Movies After Avengers 4

But there are other fan-favorites which are still waiting for their debut in the MCU. Here are heroes that deserve to enter the front-lines in Phase 4 of the Marvel Cinematic Universe and form the backbone of Avengers 5.

Nova

Nova fires his energy blasts while backed by other members of the Nova Corps

The Nova Corps, the intergalactic police force of the Marvel universe, have already appeared on-screen in Guardians of the Galaxy, but they've yet to showcase their most recognizable hero from the source material: Richard Rider.

In the comics, Rider was selected by last dying Nova Corps member Rhomann Dey (played in Guardians of the Galaxy as John C. Reilly) to replace him and given the costumes and powers of a Nova Centurion. These powers included flight, strength, speed, and the ability to redistribute absorbed energy as powerful beams of light in the comics.

Of course, given that the Nova Corps seen on-screen seem more like uniformed cops and pilots than flying superheroes, Kevin Feige and co. will have to come up with some deus ex machina to bestow said powers to a future MCU incarnation of Richard Rider. It's also not known if Rhomann Dey is still alive, considering Thanos laid waste to Xandar - home of the Nova Corps - off-screen, prior to Avengers: Infinity War in his search for the Power Stone. This is an opportune storytelling moment, though; a dying Rhomann Dey could very possibly have fled off-world to recruit Rider, and his appearance is being saved for the next phase of Marvel movies.

Read More: Did Thanos Just Create NOVA In Avengers: Infinity War?

If Avengers 5 once again finds Earth's Mightiest Heroes fighting villainy on a cosmic scale, it wouldn't hurt to pull out yet another space-set big gun from Marvel's publication history, and a character to rival Captain Marvel (who'll be getting her dues in her own solo movie and Avengers 4 next year) in terms of power.

Ironheart

Riri Williams touching the Iron-Man suit

The newest character in the Iron Man mythos, 15-year-old Riri Williams (aka Ironheart) is a genius early entrant to MIT, where she cobbles together stolen junk to make her own Iron Man costume. Eventually aided by an AI Tony Stark and Pepper Potts, encouraged to take on an Iron-mantle, Riri quickly becomes a hero in her own right.

We've already seen Tony Stark visit MIT on-screen in Captain America: Civil War, funding every project the rapt audience of students had on the go at the end of his speech. The idea that Riri could have already been in the crowd of students, ready to be inspired, is a tantalizing one.

The Tony Stark-as-mentor plot thread has already been explored through his relationship with Peter Parker, and considering he failed miserably in keeping that particular young hero alive it's unlikely that he'd be so eager for a young girl to don armor like his own. If Tony were to die in Avengers 4, however, then there'd be few people around to stop Riri from donning the mantle. Perhaps she'd even have her own AI Tony Stark around to help her (allowing Robert Downey, Jr. to pick up the easiest paychecks of his career, and still be a part of the MCU).

Importantly, this allows the Avengers to retain an Iron-clad hero, and should the character resonate with audiences, she would then perhaps gets the chance to be further fleshed out in her own solo movie.

The Sentry

Marvel's Superman-gone-psycho analog, Robert Reynolds, would be a difficult character for the movies to pull off. Reynolds is all at once drug addict Bob Reynolds, the Golden Guardian of Good known as the Sentry, and the malicious, apparently ancient biblical malevolent force known as the Void. This triple threat of conflicting personalities exists thanks to an experimental serum that Bob consumed in his efforts to get high.

In the New Avengers comics from Brian Michael Bendis, The Sentry was one of the founding members of the team, being found rotting in a prison cell on prison island The Raft, under the delusion that he had murdered his own wife. He saved the life of Foggy Nelson during the ensuing breakout (unrelated to the appearance of Matt Murdock, Luke Cage and Nelson, who are there to interview Reynolds), and assisted in taking care of crazed symbiote Carnage - by flying him into space and ripping him in two, in one of the series' cooler moments.

It was a great reintroduction to the (previously-forgotten) character and one that can easily be translated to film for Avengers 5. The saga of The Sentry and his personal quest to regain his sanity is a compelling plotline that is perhaps better saved for a New Avengers movie somewhere down the line.

Related: Marvel After Avengers 4: Everything We Know About MCU Phase 4

That said, he was never the most popular Avenger thanks to a combination of his vague powers, the Void's confusing ancient history (never adequately explained by Bendis) and Bob's continuously fluctuating mental state. It's hard for readers to cheer on a hero who either doesn't remember he is one, and/or is actually his own arch-nemesis. Marvel Studios would have to make a concentrated effort to streamline the character and his confusing biography; the upshot is that in doing so they may well finally redeem him in the eyes of fans.

Page 2: More Marvel Heroes Who Should Appear In Avengers 5

Spider-Woman

Jessica Drew is a fun link to Spider-Man, while actually not being beholden to the character. It's unclear who has the rights to the character - she could be part of Sony's ownership of Spider-Man, although didn't originate in a Spider-Man book so may bridge the gap. Whatever the case, under the Sony-Marvel deal, Spider-Woman is fair game.

Kevin Feige is sitting on a bundle of storytelling opportunities with the character, as Jessica Drew has enjoyed a fun triple-agent status, going undercover with SHIELD and later the New Avengers under pressure by Hydra (who blackmailed her by re-activating her dormant powers), but turning on Hydra by secretly reporting back to Nick Fury. Matters were complicated further when she was revealed as an impostor - the shape-shifting Skrull Queen Veranke had replaced her during her time at a Hydra research facility, and used her new standing as an Avenger to pave the way for her people's Secret Invasion - the Skrulls' attempt to turn Earth into their new homeworld (after losing theirs to Galactus). Once the dust settled and the combined heroes of Earth thwarted the attempt, the real Spider-Woman returned and became an Agent of SWORD, the space-set SHIELD offshoot.

Fans have already begun to theorize that Secret Invasion could be the plot of future Avengers movies, and the inclusion of Spider-Woman would be an important stepping stone. Arguably, the role can be filled in the MCU by other candidates, such as Black Widow, but it would still be a fun, engaging way to introduce Spider-Woman. Nick Fury, while presently a pile of dust, is sure to return, and could stand as Jessica Drew's entry into the MCU, hiring her to infiltrate a resurgent Hydra. This works doubly-well given Fury's likely role in Spider-Man: Far From Home.

Related: Captain Marvel Theory: It's Actually The MCU's Secret Invasion

She-Hulk

She-Hulk Marvel Comic Cover

When Mark Ruffalo moves on from playing Bruce Banner, there'll be a big green void to fill. Fans have been clamoring for an MCU She-Hulk appearance for some time, and her origin story is so simple that it'd be a painless process to put it on screen; Jennifer Walters is Bruce Banner's cousin and is in dire need of a blood transfusion, which she gets from Bruce, inheriting his Hulk DNA with it. However, unlike her cousin, she is mostly able to retain her intellect post-Hulk-out.

Ruffalo has one film left on his contract after Avengers 4 (assuming there haven't been any renegotiations) and even without the opportunity for a solo film (Universal own distribution rights to Hulk's standalone movies) he likely won't be around for long - and so a different take on the Jade Giant could soon be on the cards. It would be exactly the kind of fun boost the MCU needs, moving forward while maintaining something recognizable. Going for She-Hulk would also give Marvel the chance to cast another powerful, positive female role model.

Were She-Hulk to spin off into her own movie produced by Marvel following an initial, fun debut in Avengers 5, the great runs by Peter David and Dan Slott would provide a great premise; the mash-up of Jennifer Walters the lawyer and She-Hulk the superhero makes for a unique combination of bizarre superhero court cases. Her propensity to break the fourth wall also means her solo movie could rival Deadpool's in it's meta-hilarity. It would make more sense for her to appear in an Avengers movie, however, given the Universal issues.

Namor

Marvel's answer to Aquaman - who actually precedes Aquaman's creation by a good two years, at the outset of World War II - has long been considered off the table, thanks to those ever-present rights issues. Kevin Feige has said that the ongoing contractual issues are "complicated" but also admitted they are similar to the issue with the Hulk, noting they could "probably figure it out".

Related: Characters Marvel Still Doesn't Have The Movie Rights To

On the bright side, this means that everybody's favorite wing-footed sea elf could very well appear in a future MCU installment (and he was already teased in Iron Man 2). Why not Avengers 5? The film could use an antagonist, and Namor famously began as one, enacting chaos on the surface world as recompense for man's ill effects on the ocean. He later teamed with Captain America and the Allied Forces during WW2, and has been an on-again, off-again antihero ever since. This means there's already a nice redemptive arc ready for the character to utilize should he start off as a villain in Avengers 5. 

The storytelling possibilities are myriad; they could use his history as a member of The Invaders during the Second World War as a prologue, bringing him into conflict with Steve Rogers and Bucky Barnes in the present day (if one or both of them are still alive when all is said and done with Avengers 4). Then bring him back around as an ally by the film's denouement, fighting Kang, Galactus, Doctor Doom, or whichever stupidly powerful villain Marvel manage to finagle the rights to using when the time comes.

Next: Namor's New Look Is Perfect For a Marvel Movie

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