Before Kang the Conqueror was established as the central threat, several other villains could have wreaked havoc on the Multiverse Saga in the Marvel Cinematic Universe. In the wake of Thanos' defeat in Avengers: Endgame, Marvel Studios introduced a new major villain to the MCU in the form of Kang the Conqueror, setting him up as the overarching villain of the Multiverse Saga. Jonathan Majors debuted as a variant of Kang, He Who Remains, in Loki season 1, before portraying the supervillain himself in Ant-Man and the Wasp: Quantumania, but a new report suggests that Kang the Conqueror wasn't originally the MCU's heroes' next major adversary.

Speaking on the powerful Kang the Conqueror, and there are several to choose from, both from the MCU and from Marvel Comics.

12 Doctor Doom

Despite Kang the Conqueror being billed as the Multiverse Saga's villain, there is still speculation that Marvel Comics' Doctor Doom will make an appearance. Doom is one of Marvel's most recognizable supervillains, the monarch of the fictional nation of Latveria and archenemy to Reed Richards and the Fantastic Four. As a sorcerer with a genius-level intellect, Doctor Doom would have posed a formidable threat to the MCU's heroes, and since he plays a major role in Fantastic Four stories and Marvel Comics' Secret Wars, the Multiverse Saga - Phase 6 in particular - could have focused on Doom, building him up slowly in the lead up to Avengers: Secret Wars.

11 The Beyonder

While Doctor Doom was the primary villain for 2015's Secret Wars event in Marvel Comics, the original 1984 Secret Wars storyline saw a villain known as the Beyonder abduct several Marvel characters, forcing them to fight on Battleworld. With Avengers: Secret Wars set to conclude Phase 6 and the Multiverse Saga, it's possible that Marvel Studios could have been building up to the Beyonder's grand entrance. In Marvel Comics, the Beyonder is a nigh-omnipotent being from outside the multiverse, an incredibly powerful foe for the Marvel Universe's heroes who would have fit perfectly in the Multiverse Saga, as he threatened to destroy the multiverse in 1985's Secret Wars II.

10 Strange Supreme

Debuting in Marvel Studios' What If...? season 1, episode 4, "What If... Doctor Strange Lost His Heart Instead Of His Hands?" Doctor Strange Supreme was a variant of Benedict Cumberbatch's MCU hero who became obsessed with reversing an absolute point in time: Christine Palmer's death. Upon completing his goal at the expense of several beings and even another Strange variant, Strange Supreme unwittingly caused the destruction of his entire universe, though he returned as a member of the Guardians of the Multiverse. Doctor Strange in the Multiverse of Madness teased more villainous variants of Doctor Strange, so this could have been an interesting story for the MCU's Multiverse Saga to follow.

9 Mephisto

As the ruler of Marvel Comics' version of Hell, Mephisto is one of the most prominent supervillains in the Marvel Universe, so it's only a matter of time until he's introduced to the MCU. During WandaVision's release as part of the MCU's Phase 4, many theories arose suggesting that Mephisto would debut during the MCU's first Disney+ series, and although this didn't come to fruition, this could have set the stage for him to be a looming presence in the Multiverse Saga. Rumors now suggest that Mephisto could debut in Ironheart, so it's possible that Marvel Studios may refocus the Multiverse Saga to feature the demon as its primary villain.

8 Infinity Ultron

Whereas the MCU's live-action Ultron was defeated by the Avengers in Phase 2, What If...? explored a universe in which the artificial intelligence managed to himself into the Vision's body and beat Earth's Mightiest Heroes. During What If...? season 1, episode 8, "What If... Ultron Won?," the titular supervillain wreaked havoc not only in his home reality but across the entire multiverse, which could have set up the perfect threat for the live-action heroes in the MCU's Multiverse Saga. Many criticized Avengers: Age of Ultron's lackluster depiction of the iconic Marvel villain, so the Multiverse Saga may have posed the perfect opportunity to redeem him.

7 Loki

First introduced in 2011's Thor, Tom Hiddleston's Loki saw a huge redemption arc throughout his MCU journey, culminating in his tragic death in the opening moments of Avengers: Infinity War. However, the Avengers' Time Heist released a version of Loki from 2012, immediately following the Battle of New York. While this variant went on to become a hero in Loki on Disney+, freeing a more villainous, past version of Loki could have opened the door for him to pose a greater threat to the Multiverse Saga's heroes - especially since he gained access to the Time Variance Authority and its multiversal resources.

6 Galactus

Following the confirmation that the Fantastic Four would be coming to the MCU, speculation rose about whether Marvel Comics' Galactus would be featured as the film's villain. A giant cosmic entity, Galactus and his Heralds - including the Silver Surfer - scour the universe, searching for planets for him to devour to sustain his life force. Galactus is a monumental threat to the Earth of the Marvel Universe and would have made a fantastic and morally complex major villain for the MCU's Multiverse Saga. Since he first appeared in a Fantastic Four story in Marvel Comics, it's possible that Phase 6's Fantastic Four could mark his MCU debut.

5 Annihilus

If not Galactus, Annihilus is also a popular choice for the villain of the MCU's Fantastic Four project, as the ruler of the Negative Zone regularly butts heads with Marvel's First Family in Marvel Comics. Annihilus was featured as the primary antagonist of 2006's Annihilation storyline, which saw him send his powerful Annihilation Wave into Marvel's main universe, leaving a trail of destruction in its wake. This event could have been a great story to tell in the MCU's Multiverse Saga, particularly since the Negative Zone has been teased in the MCU for several years already, so perhaps Fantastic Four will finally pay these hints off.

4 Mister Sinister

Much like the Fantastic Four, mutants and the X-Men were teased for the MCU after Disney's acquisition of Fox in 2019, and Marvel Studios started their slow introduction of mutants in Phase 4. One of the greatest threats facing mutant-kind in Marvel Comics is Mister Sinister, formerly known as Nathaniel Essex. Sinister was a genetic scientist obsessed with engineering humanity into the perfect race of superhumans, so the rise of mutants instantly fascinated him. In Marvel Comics, Sinister inspired the genetic work of the High Evolutionary, so Guardians of the Galaxy Vol. 3 could have hinted at the existence of the X-Men villain, though this didn't come to .

3 Scarlet Witch

Elizabeth Olsen's depiction of Wanda Maximoff in the MCU has taken her on a tumultuous journey. Wanda has ggoner from unwitting HYDRA volunteer to Avenger, to fugitive, to villain, to the multiverse-threatening Scarlet Witch. While WandaVision teased the Scarlet Witch's villainous descent, Doctor Strange in the Multiverse of Madness showed her fully bringing chaos to the multiverse, massacring Earth-838's Illuminati team. While she apparently met her demise in Multiverse of Madness, many expect the Scarlet Witch to return in the MCU's future, and she could do so as the new major villain of the Multiverse Saga, potentially having a huge role in Avengers: Secret Wars.