With Avengers: Endgame now behind us, fans of the MCU are looking ahead to the future of the cinematic universe. While it's fun to speculate on which heroes will be headlining the future of the MCU, there's a lot of great villains to speculate about as well.

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The MCU once had a major villain problem, constantly pumping out dull and forgettable foes for our heroes to face for one movie, then never to be seen again. In the more recent years, they have managed to turn things around and create a number of compelling baddies. There's still so many Marvel villains we'd love to see brought to the big screen, but there's also some great ones still lurking around in the MCU. Here are a few bad guys we'd love to see again.

10 10. Red Skull

Red Skull has always been Captain America's most iconic foe so it makes sense he was the adversary in Cap's first MCU film. At the end of The First Avenger, Red Skull is sucked up into space by the Tesseract. That was the last we saw of him until he made his return in Infinity War as Stonekeeper of the Soul Stone.

It's a little confusing what Red Skull's involvement can be going forward. Since Cap returned all the Infinity Stones, is Red Skull still bound to serve on Vormir? The filmmakers have said he's now a ghost of the man he once was, but there is still a possibility he could become a cosmic threat at some point.

9 9. Justin Hammer

Justin Hammer might not be the most intimidating villain the MCU has produced, but thanks to Sam Rockwell's performance, he is one of the most entertaining. Hammer was sort of a secondary antagonist in Iron Man 2, although we can't help but wonder if that film would have been better with him front-and-center.

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Hammer is imprisoned at the end of that film and hasn't been seen since aside from brief appearance in a One-Shot which confirmed he's still in prison. It would be great to see him get out eventually as he would make a great villain for Ant-Man and the Wasp to face.

8 8. Helmut Zemo

Zemo in Captain America: Civil War
Marvel's Captain America: Civil War..Zemo (Daniel Brühl)..Photo Credit: Zade Rosenthal..© Marvel 2016

Zemo is another of Captain America's main villains from the comics to make it into the MCU. Though missing his famous purple hood, Zemo appeared in Civil War as the trouble-maker behind the superheroes fighting each other. He was a small, but pivotal role in that film and was incarcerated by the end.

Zemo proved to be quite the mastermind in Civil War and it would be great to see what else he had up his sleeve. It appears as though we might get our wish to see more of him soon as he is rumored to be returning for The Falcon & The Winter Soldier series on Disney+.

7 7. Mordo

Karl Mordo looking grim in the MCU

Baron Mordo is a key villain for Doctor Strange and a frequent servant of Dormammu. However, in Doctor Strange's first solo film, Mordo was one of Strange's closest allies. He is a fellow sorcerer and loyal follower of the Ancient One until he find out his mentor has used dark magic for her own purposes.

By the end of the film, Mordo abandons the path of the sorcerer supreme and sets out to rid the world of those who possess the mystic arts. This end for the character seems to set him up perfectly for the next Doctor Strange film which is said to be part of Phase 4.

6 6. Ayesha

Ayesha Lamest MCU villains

Ayesha is the High Priestess of the Sovereign, a genetically engineered race who see themselves as superior to all others in the universe. In Guardians of the Galaxy Vol. 2, Ayesha seeks to destroy the Guardians for stealing from the Sovereign and insulting them. The Guardians succeed in decimating her army, but in the post-credit scene, we see she has created a new being to stop them; Adam Warlock.

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It's unclear if Adam Warlock will be included in Guardians of the Galaxy Vol. 3, but if he is, it's safe to assume Ayesha will make her return again. If not, she is a character who could conceivably appear in any cosmic adventure of the MCU.

5 5. Abomination

Abomination

The Incredible Hulk is likely the most forgotten of the MCU's films, but it did give us a fairly memorable villain with Abomination. A frequent foe of Hulk in the comics, Abominaton is the creature that Emil Blonsky becomes attempting to match Hulk's power. He is eventually defeated by Hulk and taken into custody by General Ross.

A solo Hulk film does not seem to be a high priority for the MCU, and given the complicated rights issues, it's unlikely we'll see one soon. But with such a powerful villain still out there, it seem like only a matter of time before Abomination is reintroduced.

4 4. The Vulture

For Spider-Man's first solo adventure in the MCU, they wisely went with a member of his Rogue's gallery who had yet to appear on the big screen. While Homecoming's version of Vulture was quite different from the comic book iteration, he proved to be a memorable villain. Michael Keaton was fantastic in the role and there was a great twist with the character as well.

Though Vulture was put in prison at the end of the film, he's confirmed to be involved in Spider-Man: Far From Home. It remains to be seen if he'll have turned over a new leaf or if he'll continue his villainous ways -- perhaps as part of the Sinister Six.

3 3. Yon-Rogg

Jude Law in Captain Marvel

The Kree-Skrull War was a key storyline in Marvel comics and Captain Marvel brought it to the big screen, albeit on a smaller scale. But in a clever twist, the Skrull, who are typically villains in the comics, were shown to be victims of the Kree's tyrannical rule. This led to the reveal that Yon-Rogg, Carol Danvers' mentor, was a villain all along.

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Yon-Rogg is spared by Carol and sent back to the Kree homeworld after being defeated. It makes sense that he and the other Kree might seek revenge on Captain Marvel or perhaps invade Earth again.

2 2. The Mandarin

Mandarin Ben Kingsley Iron Man 3

One of the most controversial choices the MCU has ever made was their re-imagining of The Mandarin in Iron Man 3. The character was Iron Man's main foe in the comics and was seen as a powerful and evil mastermind. The film portrayed him as a drunken actor playing to role of a criminal for the film's real villain, Aldrich Killian. Some found it a clever and hilarious take on the character while others found it to be a major letdown.

We find out in a Marvel One-Shot that there is in fact a real Mandarin lurking out there somewhere. Kevin Feige recently confirmed that the character would appear at some point in the future.

1 1. Dormammu

Perhaps the most powerful villain he have seen in the MCU to date is Dormammu. The lord of the Dark Dimension, Dormammu's powers and abilities rival just about any being in the Marvel universe. He was almost unleashed on the realm of the living in Doctor Strange until Strange trapped him in a time loop and barred him from his conquest.

A character as evil as Dormammu will likely not take such a defeat lightly. Chances are he'll make another attempt at taking over the other dimensions before long. He might even be a villain worthy of reassembling to Avengers to fight against.

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