Fans were overjoyed at this year's San Diego Comic-Con when Marvel Studios finally revealed their upcoming Phase 4 of the Marvel Cinematic Universe. And while the Phase 4 announcement didn't include any of Disney's recently acquired 20th Century Fox properties, they did reveal that they were making plans for the Fantastic Four to join the MCU.

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We've seen the Fantastic Four on the big screen a few times now, though the films had a severe lack of successful villainry, with watered-down versions of Doctor Doom failing to impress fans or doing the character any justice. With Doctor Doom pretty much a given for any future Fantastic Four appearance in the MCU, today we are going to take a look at a few other Fantastic Four villains we want to see in the MCU.

10 MOLE MAN

The very first villain Marvel's first family of comics ever faced was the Mole Man, the human ruler of an underground kingdom with an army of Moloids and a number of gigantic monsters under his command. Following the team's transformation into the Fantastic Four, they were forced to protect New York from a giant monster sent by Mole Man.

Giant monsters go hand in hand with the Fantastic Four, yet we have never seen the team face anything like that in the three cinematic outings from Fox. Using the Mole Man to facilitate any kind of giant monster battle with the FF will cement the MCU's version of the team as the best adaptation of the comic, despite what happens in the rest of the film. Giant monsters or bust, Marvel.

9 FRIGHTFUL FOUR

We'll be honest, the Frightful Four are not the most fearsome or intimidating of villains for the Fantastic Four to face, but that isn't necessarily a bad thing. The Frightful Four is made up of a number of b-list villains who occasionally jump a few levels when they work together, which brings them into conflict with their heroic counterparts, the Fantastic Four.

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Led by the Wizard, the team has included characters like Sandman, Medusa, Thundra, Hydro-Man, Titania, and more. Of course, any inclusion of the Frightful Four needs to have classic member Paste-Pot Pete/Trapster along purely for comedic effect. However, there is another member of the team who could get his own starring role as a villain...

8 KLAW

Fans might recognize the name/character of Klaw, though in the MCU he is better known as Ulysses Klaue and is deceased after the events of Black Panther. Comic fans know that death never really stopped Klaw, whose exposure to Vibranium and his own sonic gun invention forever altered his form into one of pure sound.

Klaw often faced off against the Fantastic Four and has died and been reborn a number of times thanks to his attachment to his sonic hand weapon. That same weapon was seen in Black Panther, though his evolution into a sonic form never technically happened. Regardless, the character would provide a fantastic callback to the rest of the MCU while giving the team a visually impressive villain debut with.

7 RED GHOST & THE SUPER-APES

Okay, there might be some chuckles here, and we agree, Red Ghost and the Super-Apes sound a little ridiculous. However, depending on which origin story the MCU chooses to use to explain the Fantastic Four, Red Ghost and his Apes could provide the perfect dark mirror to develop opposite the FF.

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Ivan Kragoff/Red Ghost was a USSR Cosmonaut who was sent on a similar mission as the Fantastic Four, though instead of friends and family he was on a shuttle with three apes he had spent years training. They were bombarded with the same cosmic rays as the FF and given incredible powers, which Red Ghost mainly used to try to take control of the moon and prove his superiority over the FF.

6 PSYCHO-MAN

Psycho-Man vs the Fantastic Four

When looking at already established MCU connections that could be used to further cement the Fantastic Four's position in the Marvel Cinematic Universe, one recently introduced location stands out above the rest - the Quantum Realm. While it is never referred to it this way in the MCU, the Quantum Realm is actually the cinematic equivalent of the Microverse.

The Microverse features a number of threats that the FF protect the Earth from, including Psycho-Man, who wants to take over Earth in order to save his worlds from overpopulation. The real danger and story potential with Psycho-Man comes from his manipulation and control of emotions, which would allow filmmakers a chance to explore the FF in a unique way for their MCU debut.

5 SUPER-SKRULL

Super Skrull with the Fantastic Four

We've now seen the Skrulls appear in the MCU a couple of times (that we know of) beginning in Captain Marvel, and most recently in the post-credits of Spider-Man: Far From Home. And while the MCU Skrulls are working with Nick Fury and appear to be allies, without knowing much more about the time gap between their two appearances, we aren't fully satisfied that all of the Skrull are allies.

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In the comics, the Fantastic Four found themselves fighting their own abilities when they first encountered Kl'rt the Super-Skrull. Formerly a decorated Skrull warrior, Kl'rt volunteered to be genetically modified with the abilities of the FF to become the Super-Skrull, a process later used to power up a number of other Super-Skrulls during Secret Invasion.

4 KANG THE CONQUEROR

Kang the Conqueror is likely not unknown to fans of the MCU, as he has been rumored to appear against the Avengers for years, especially with the recent introduction of time travel into the MCU. however, Kang has an incredibly wide reach in the Marvel Universe and has as much history with the Fantastic Four as he does the Avengers.

The Fantastic Four first ran into the time-traveling Pharoah Rama-Tut (and later the Scarlet Centurion) in ancient Egypt, and then later the Master of Time Immortus and his timeless realm of Limbo. Eventually, they would also encounter Kang the Conqueror, and discover that all of these individuals were actually the same person from different points in his timeline. Twist!

3 NAMOR

Another long-rumored addition to the MCU is Namor the Sub-Mariner, King of Atlantis. The Atlantean mutant (it's true) was one of the Marvel Universe's first creations back when they were known as Timely Comics. Namor would later appear in the pages of Fantastic Four and often toes the line between hero and villain.

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While there are some film rights issues that remain with Namor's inclusion in the MCU, any Fantastic Four adaptation would be the perfect place to introduce the Atlantean King and wishful-suitor of Sue Storm/Invisible Woman. Since we may have already heard of a tease of Atlantis in Avengers: Endgame, the time might be right for Namor to appear alongside the FF.

2 GALACTUS

Galactus History Marvel Universe

One of the best gains by Marvel from their deal with 20th Century Fox (alongside the X-Men) is the film rights to one of the biggest (both figuratively and literally) villains the Fantastic Four have ever faced - Galactus.

The Devourer of Worlds has been seen previously in Fantastic Four: Rise of the Silver Surfer, though the cinematic interpretation of the character was lackluster. Hopefully and plans by Marvel Studios to adapt Galactus will give the character the respect a threat of his magnitude deserves, and potentially even make him the next big MCU baddie along the same lines of Thanos.

1 ANNIHILUS

Annihilus demonstrates his rage

Galactus may be a great potential option for the MCU's next big bad, but the FF have another villain who was at one point an even bigger threat to the Marvel universe than Galactus. The creature known as Annihilus hails from the Negative Zone, an alternate anti-matter reality discovered by Reed Richards.

During the Annihilation event, Annihilus and his armies (known as the Annihilation Wave) began invading the Marvel universe, causing heavy casualties that resulted in the formation of galactic alliances and teams like the modern Guardians of the Galaxy. Annihilation is a probable next step for the MCU, so introducing Annihilus early alongside the Fantastic Four would help kick off the next big event films.

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