Benedict Cumberbatch will be back as Doctor Strange in 2022 with Doctor Strange in the Multiverse of Madness, but what starts the titular multiverse of madness? Doctor Strange was last seen returning from the dead in Avengers: Endgame, helping the combined heroes take on Thanos and his forces as the Mad Titan pursued the Infinity Stones for the last time.

Shortly after Avengers: Endgame hit theaters, Kevin Feige - President of Marvel Studios - announced the upcoming slate of the Marvel Cinematic Universe, and the enigmatically-titled Doctor Strange in the Multiverse of Madness was among them. The film's title has created palpable intrigue as fans debate what 'Multiverse of Madness' actually means for the character and the MCU at large.

Related: Doctor Strange 2 Should Introduce A Multiversal X-Men Villain

Marvel fans will already be familiar with the concept of the Multiverse; a series of alternate Earths and parallel universes, where the differences can be infinitesimally small or devastatingly huge. Marvel Studios' first animated show What If? will explore a number of these divergent timelines, including Peter Parker becoming Hawkeye and Peggy Carter becoming Captain America. Doctor Strange 2 presumably sends Doctor Strange hurtling through the multiverse, fighting and finding his way back to his own earth, most likely saving said multiverse in the process. But what will cause Doctor Strange's journey through the multiverse? What starts the 'multiverse of madness'? Here are all the established theories so far.

Scarlet Witch

Scarlet Witch Doctor Strange and the Multiverse of Madness Villain Theory

It's already been announced that Wanda Maximoff - the Scarlet Witch - will be appearing alongside Doctor Strange in Doctor Strange in the Multiverse of Madness, following her appearance in Disney+ show WandaVisionFrom the brief glimpses of WandaVision that audiences have already seen, Wanda seems to be living multiple lives with her deceased lover Vision in some kind of warped reality/dream state.

This has led to the theory that Wanda is either already jumping through the multiverse in WandaVision, or she has been trapped in a dream by an enemy (see Nightmare, below) or that she has lost her mind with grief and begun to create alternate realities all by herself. It's likely that Scarlet Witch is the cause of the multiverse of madness due to her marquee appearance in the sequel, in addition to her history of creating alternate timelines - like the House of M - in Marvel Comics, thanks to her reality-warping powers. If Marvel Studios were to utilize the House of M alternate reality, they could even finally bring the X-Men into the MCU.

Other evidence attributed to Scarlet Witch being the cause of the multiverse of madness stems from Doctor Strange's indirect responsibility for Vision's death in Avengers: Infinity War. After giving up the Time Stone to Thanos, the Mad Titan immediately headed to Earth where he ripped the Mind Stone from Vision's head, killing him. Wanda Maximoff could desire revenge for Doctor Strange's hand in her boyfriend's death, which may then lead to the Multiverse of Madness.

Related: Doctor Strange 2 Theory: Scarlet Witch IS The Multiverse Madness

Loki

MCU Theory Loki is key to the Multiverse of Madness

Loki is due to appear in his own Disney+ show Loki, following the events of Avengers: Endgame; could that be a stepping stone to becoming the villain of Doctor Strange in the Multiverse of MadnessNews has already broken that his self-titled show will center around the 2012 version of Loki that escaped with the Tesseract after the Avengers' time-travel flub, and with the Space Stone unwittingly in his possession, 2012 Loki can jump around the universe wherever he wants.

Recent images have shown Loki as a prisoner of the Time Variance Authority - the police in charge of protecting the timestream from meddling - after moving through time. Concept art has shown Loki in New York in the 1970s, and the time cops are likely not too happy with his interference with the time/space continuum. Could such meddling result in a multiverse of madness? What's certain is that 2012 Loki is not meant to exist outside of that timeline. 2019 Loki was killed by Thanos, and Captain America returning all the Infinity Stones to the points where they were taken means that Loki never should have escaped. Loki's continued survival means chaos for the multiverse, as explained by the Ancient One in Avengers: Endgame; consider him a strong contender for the cause of the titular madness in Doctor Strange in the Multiverse of Madness.

The Avengers

Doctor-Strange-and-Iron-Man-in-Avengers-Infinity-War

The Avengers themselves may have been the cause of the events of Doctor Strange in the Multiverse of Madness. As the Ancient One explained to Smart Hulk in Avengers: Endgame during their 'time heist' of the Infinity Stones, if one of the Stones is removed from its place in time it can cause that reality to branch off and lose balance. This would create a darker, splinter reality. Smart Hulk counters this ominous prophecy by suggesting that the Avengers return the Stones to their original place in the timeline when done with them in their present, thereby restoring balance. The Ancient One is finally persuaded when informed that Doctor Strange willingly surrendered the Time Stone to Thanos, as he wouldn't have done that if there were no other way.

Regardless of the fact that Captain America returned all the Infinity Stones to whence they came following Avengers: Endgame (resulting in a presumably awkward interaction with Red Skull), each stone was still removed from the place in space and time they were supposed to be. It could be possible that the removal of the Time Stone - not to mention the others - led to the fracturing of realities that the Ancient One warned of. Disturbingly, this would mean that the Avengers might be responsible for the start of the fracturing of the multiverse in Doctor Strange in the Multiverse of Madness.

Related: Doctor Strange 2 Theory: The Multiverse Madness Is Motivated By Infinity War

Thanos

Thanos and Doctor Strange in Avengers Endgame

The Ancient One warns Smart Hulk that the removal of the Time Stone (as well as the other Infinity Stones) leaves the universe defenseless against any number of threats. What would she have to say when she learns that Thanos decided to destroy all the Stones after successfully using them to wipe out half of all life in the universe? One theory is that Thanos' destruction of all the Stones removes the very bedrock of creation, thus potentially leading to chaos and danger in the entire multiverse. If Thanos' destruction of the Infinity Stones leads to the multiverse collapsing in on itself - a true Multiverse of Madness - Doctor Strange will need all the help he can get in Doctor Strange in the Multiverse of Madness.

Dormammu

Doctor Strange talking to Dormammu

In Doctor Strange, the Sorcerer Supreme was able to best the Dread Dormammu by trapping him in an endless loop of being confronted by Strange and murdering him, over and over again. This forced Dormammu to promise never to attack Earth again, and the multidimensional being is bound by his word; that doesn't mean that fans will never see him again. If Dormammu returns for Doctor Strange 2, he could be getting revenge on him by way of causing the multiverse madness.

Nightmare

Doctor Strange 2 Nightmare and Shuma Gorath

When Scott Derrickson was still due to direct the then-unnamed sequel to Doctor Strange (he has since been replaced by Sam Raimi) he was vocal about having Nightmare be the villain. Nightmare was intended to be the villain of Doctor Strange, but was considered too exposition-heavy. Marvel fans will recognize Nightmare as the ruler of the Dream Dimension, and is rather fond of putting Strange through all manner of trials and tribulations for his own amusement. Scott Derrickson may have managed to install Nightmare as the villain before his amicable departure from the director's chair; he is remaining on as an Executive Producer so it's possible he can still exert some kind of influence over Doctor Strange in the Multiverse of Madness. Nightmare would make sense as the cause of the Multiverse of Madness.

If the events of Doctor Strange in the Multiverse of the Madness are a follow-on from WandaVision, one theory (further explained on MovieWeb) goes that Nightmare is responsible for sending Wanda Maximoff into repetitive fantasies of a picturesque life with her dearly-departed Vision. The brief footage seen from WandaVision show Wanda and Vision in a number of different sitcom-esque scenarios. This could be the Dream Dimension in action; when combined with Wanda's reality-altering powers, it could be the start of Doctor Strange in the Multiverse of Madness. However, with Derrickson gone from the director's chair, Nightmare's inclusion now looks less likely.

Related: Did Infinity War Changes Ruin Doctor Strange’s ORIGINAL Villain?

Doctor Doom

Doctor Strange and Doctor Doom

Following the Disney acquisition of 20th Century Fox, the cinematic rights to the Fantastic Four and their villains are finally back home at Marvel Studios. This means that fan-favorite villain Doctor Doom can finally be introduced to the MCU, especially considering his previously-announced solo movie under Noah Hawley's direction is "in limbo" after the merger. With production on Doctor Strange in the Multiverse of Madness paused due to the COVID-19 outbreak, it's not too late for Marvel to retroactively include Doctor Doom as the cause of said madness now that they have him back in their stable.

At this point, any theory pointing to Doctor Doom being the villain in Doctor Strange in the Multiverse of Madness is pure speculation. The emphasis on Doctor Doom as a sorcerer first and a scientist second in his currently ongoing comic book series suggest that an appearance in the Doctor Strange franchise could be a fitting first step for Doom in the MCU. His magical abilities could certainly assist in ripping through the multiverse, but time will tell if Doctor Doom is the cause of the events of Doctor Strange in the Multiverse of Madness.

Next: Doctor Strange 2: Why Black Knight Should Be In The Multiverse Of Madness

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