While the Marvel Cinematic Universe has done a masterful job of bringing so many iconic comic book characters to the big screen, the long and storied history of Captain America leaves a deep well of supporting players yet to be seen. Over the decades, Steve Rogers and the other Captain Americas have encountered a fascinating cast of allies, rivals, and outright villains who offer unique stories that could easily be adapted for the MCUโs future. From characters with complicated connections to Cap’s past to powerful figures with a code of honor all their own, these individuals could spark new avenues in the MCU.ย
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Whether they’re heroes, villains, or somewhere in between, these seven characters represent some of the most exciting potential additions to the MCU.
1. Sin (Sinthea Shmidt)

The daughter of the Red Skull, Sinthea Shmidt, was raised to be her father’s heir. Originally a mind-controlled assassin, she was later de-aged and stripped of her powers, eventually becoming a terrifying, unmasked villain. She has been a consistent thorn in the side of multiple Captain Americas, and her villainous deeds often carry a brutal, personal grudge against Steve Rogers and his personal legacy.
Sin’s storyline as the new Red Skull and her role in major comic events like “Fear Itself” would be a fantastic way to bring back a powerful legacy villain. She could serve as a dangerous and unpredictable force, capable of leading her own splinter faction of Hydra or other evil organizations. A legacy villain with a direct connection to the MCU’s first big bad would be a perfect way to expand on the Red Skull’s lasting influence.
2. Union Jack (Joseph Chapman)

One of the many characters to hold the mantle of Union Jack, Joseph Chapman was a working-class hero who became a vigilante after being inspired by the original. He is known for his street-level fighting skills and his iconic Union Jack costume, making him a symbol of British patriotism and heroism, like Steve Rogers in America. Unlike many superheroes, he relies on his physical skills and combat abilities rather than powers.
Introducing Union Jack would give the MCU a grounded, street level hero from a different country, allowing for a look at how other nations view and deal with the rise of superhumans. Union Jack could be used to explore a more working-class perspective on heroism and patriotism. He would be a great character to team up with Captain America or even characters like Black Widow or Hawkeye on a more grounded, international mission.
3. Jack Flag

Jack Harrison, better known as Jack Flag, was a patriotic man inspired by Steve Rogers’ Captain America. After a run-in with the Serpent Society left him with superpowers, he took on the identity of Jack Flag with the intention of honoring his idol. Heโs had a complicated comic book history, serving as both a solo hero and a member of different teams, including the Guardians of the Galaxy.
Bringing Jack Flag to the big screen would add a character who truly represents the idealistic, fan-turned-hero stereotype. His story could show the consequences of trying to live up to a hero’s legacy without the same level of training or experience. This could make an interesting contrast to the more jaded heroes of the MCU and create a powerful character arc as he blazes his own path.
4. Vagabond (Priscilla Lyons)

Priscilla Lyons was an ex-policewoman who became a crimefighter inspired by Captain America’s former partner, Nomad. As Vagabond, she joined forces with Cap and Nomad to fight against a laundry list of villains. Her backstory and skills are grounded in a realistic, street-level context like Daredevil and Jessica Jones, making her not only a unique addition to the lineup of heroes, but one that has the potential to thrive in the Disney+ corner of the MCU.
Her background as a police officer would make her a fascinating figure to follow as she navigates the blurred lines between justice and vigilantism, as so often explored in series about The Defenders. She would offer a fresh perspective on the superhero world while fitting in seemlessly with the likes of Daredevil, Luke Cage, Jessica Jones, and Danny Rand.
5. Ameridroid

The Ameridroid is a bizarre, but memorable, Captain America villain. In his final moments, a Nazi scientist named Lyle Dekker transferred his consciousness into a massive, 18-foot-tall android replica of Captain America. The “Ameridroid” had all of Captain America’s abilities, only made more dangerous by its sheer size.
The Ameridroid is the kind of outlandish and straight-from-the-comic-pages villain that could work perfectly in the MCU, adding a bit of flash and madness. It could be used to explore the lasting threat of HYDRA in a creative way, much like the way Armin Zola was portrayed in Captain America: The Winter Soldier. Captain America fighting a gigantic, evil version of himself would be an unforgettable moment on screen.
6. Nomad (Jack Monroe)

Jack Monroe was a forgotten “Bucky” from the 1950s who, after being put in suspended animation (much like the real Bucky), was reawakened and cured of his brainwashing. He then took on the mantle of Nomad, a hero who had no country or political allegiance. Monroe’s Nomad was an important supporting character for Captain America, even acting as his partner for a time.
Nomad’s story as a disillusioned hero with no country was explored only superficially with Steve Rogers after the events of Captain America: Civil War. Having him interact with the unfamilar modern-day world would create a thematic parallel to Steve Rogers’ own experience. He could be a great character to explore the gray areas of morality and whether a hero’s allegiance should be to an idea or a nation.
7. Baron Blood (John Falsworth)

John Falsworth, also known as Baron Blood, is a vampire who has terrorized England for centuries. He is an arch-nemesis of the original Union Jack and a recurring member of Captain America’s rogues gallery during World War II. His origin as a British aristocrat turned undead supervillain is something that has not been seen in the MCU.
Bringing Baron Blood into the MCU could bring a supernatural, horror-tinged element to the MCUโs Captain America stories, similar to how Doctor Strange in the Multiverse of Madness explored that side of the universe. He would be a great way to explore a villain with a deep historical grudge against both a Captain America and a Union Jack. Being a centuries-old villain who is also a vampire would set him apart, creating a fresh and chilling challenge for the heroes.