Some of the most interesting villains in fiction have spawned from Marvel Comics. While these villains have gained greater recognition after starring in popular Marvel films, their greatest forms still lie in the pages of their comic book origins. In comics, nothing is impossible, and Marvel comics frequently explore countless possibilities while asking, "what if this or that happened?"
The Marvel multiverse contains some truly powerful beings who wield reality-breaking weapons and artifacts. And some creative writers and artists at Marvel explore the possibilities of popular villains obtaining these weapons and artifacts. They ask, what would happen if a villain reached their fullest potential? As proven in many stories, they'd be unstoppable.
10 Doc Ock Becomes The Superior Octopus
In The Amazing Spider-Man #700, Otto Octavius finally won. He not only defeated Spider-Man but switched bodies with him. While Peter's mind died in Otto's body, Otto's mind thrived in Spider-Man's. But with great power comes great responsibility, and Otto's time in Spidey's shoes slowly turned him into a hero.
After the events of Clone Conspiracy, Otto once again transferred his mind into a body that was part-Otto, part-Peter. In this new body, Otto fused his mind with Peter's powers and became the Superior Octopus. Doc Ock was always a powerful villain, but Superior Octopus is by far his strongest form.
9 All Hail God King Doom
In the 2015 Secret Wars event, the main Marvel 616 universe and Ultimate universe collided. Doctor Doom used the powers of the Beyonders to create Battleworld, a planet slapped together using bits and pieces of the colliding universes. Here, Doom was known as God-King Doom or God Emperor Doom. He was all-powerful and ruled over everything.
With the Beyonders' powers, Doom achieved a level of omnipotence. He held the fragments of Battleworld together, changing reality, space, and time to fit his desires. Doom always wanted to create a utopia that he could rule and he finally had the power to do so.
8 The Mind & Powers Of Xavier & Magneto Create Onslaught
Charles Xavier works to achieve mutant acceptance whereas Magneto strives for mutant superiority. During one of their confrontations, Xavier hit Magneto with a powerful psychic blast. Parts of Magneto's mind latched onto Xavier's, making Xavier's inner demons rise to the surface and a new persona emerge in the form of Onslaught.
Onslaught is the combination of every aspect of Xavier and Magneto. Onslaught shares their powers of telepathy and magnetism, as well as their views of mutant acceptance and superiority. Xavier and Magneto are two of the most powerful mutants, making Onslaught a force to be reckoned with.
7 Astral Regulator Thanos Is The Strongest Thanos
First appearing in Thanos: The Infinity Conflict #1, an Astral Regulator is a device created by the One-Above-All, the most powerful cosmic being in the Marvel multiverse, to maintain order and structure across the multiverse. There is an Astral Regulator hidden in each universe and Thanos found the one in Earths.
Guided to its location by his future self, Thanos obtained the Astral Regulator and absorbed it into his body. This fusion gifted him the powers of the Living Tribunal, who is the second most powerful being in the Marvel universe. Therefore, Thanos temporarily had more power than all the Infinity Gems combined.
6 Carnage And Osborn Bond To Create The Red Goblin
In order to rid himself of microscopic nanites, Norman Osborn bonds with the Carnage symbiote. After the symbiote destroys the nanites, Osborn ingests the Goblin formula, melding the Green Goblin and the Carnage symbiote into one and the Red Goblin was born.
The merging of Osborn and Carnage was Peter's worst nightmare. The villain targeted nearly all of Peter's loved ones and closest allies. The Red Goblin was seemingly more powerful than most symbiotes and impervious to fire. He could also create symbiotic pumpkin bombs and could even infect others with the symbiote, as he did with Normie.
5 Red Skull Becomes Red Onslaught
The Red Skull has used the Cosmic Cube, but even that power is insignificant compared to the power he possessed as Red Onslaught. In the AXIS comic event, Magneto tried to kill the Red Skull but inadvertently melded Red Skull with the psychic entity known as Onslaught.
Though not as powerful as any of the cosmic beings like Galactus or the Living Tribunal, Red Onslaught is still one of the most powerful villains the X-Men and Avengers have ever faced. Red Onslaught possessed one of the most powerful telepathic minds. He could alter, infect, or destroy other people's minds with his own.
4 Doom, The Annihilating Conqueror
Kang the Conqueror is one of the Avengers' oldest foes. He first appeared in Avengers #8, published in 1964. Kang has had many names and alternate personas but he has always been known as the Master of Time. Kang was a being from the future who would use his knowledge to dismantle the Avengers. He is notoriously difficult to defeat as a future version of himself could always return.
In one timeline, Kang merged with Doctor Doom and Annihilus to become Doom, the Annihilating Conqueror. In this form, Kang not only had access to his usual forms of time travel and time manipulation, but he controlled the powers of Doom and Annihilus as well.
3 Galactus Gains The Power Of Dormammu
Galactus is known as a world eater. He controls the Power Cosmic and is able to gift fractions of that power to beings that become his heralds. Silver Surfer is one of Galactus's many heralds and is also one of the most powerful Marvel heroes because of that title. Needless to say, Galactus does not need any more power.
Unfortunately for the Marvel heroes, in 2019's Doctor Strange #15, Galactus absorbs the essence of Dormammu and gains control over the Dark Dimension. For a short time, Galactus controls the Power Cosmic and has mastery over dark magic. Thankfully, his ego gets the better of him, so his upgrade doesn't last long.
2 Loki Becomes King Of Asgard
Written by Robert Rodi and illustrated by Esad Ribic, the 2004 Loki miniseries presents an alternate reality in which Loki wins. In this universe, Loki has defeated Thor and Odin and claimed the title of Ruler of Asgard. This is Loki either at his best or worst, depending on how you look at it.
The story begins with Loki already on the throne and follows the efforts of Thor and a resistance team who attempt to dethrone their new king. The playful trickster Loki fans may be used to is replaced with a more malevolent, stern ruler. This version of Loki is more terrifying and holds more power and authority than any other Loki.
1 Ultron Possesses The Powers Of Odin
Created by Al Ewing and Alan Davis, the Avengers: Ultron Forever storyline explores a potential future where an advanced version of the Ultron virus spreads across the globe and proves too much for the Avengers of the future. Ultron conquered the galaxy and extended his reach to other realms, including Asgard.
With Loki's help, Ultron killed Odin and claimed the Power of the All-Father. This was by far the most powerful version of Ultron. Along with his usual, cybernetic abilities, Ultron possessed the god-like powers of Odin. This god version of Ultron was only defeated by Doctor Doom and a team of powerful Avengers from other universes.