Much has been said lately about Doctor Doom's followers in Avengers: Doomsday, including a "wizard sidekick" who wears a mask with a slit for a third eye on his forehead.
As of now, all signs point to Doctor Strange breaking bad and allying himself with Victor Von Doom. When we last saw the former Sorcerer Supreme, it seemed that his travels through the Multiverse—and the Darkhold powers he'd accessed to save the day—had started pushing him down a dark path.
In a post-credits scene, Strange met Clea, a character who could have quite easily opened his (three) eyes to the benefits of utilising new kinds of magic. Plus, let us not forget that Doom wields magic just as easily as he does science.
Today, Murphy's Multiverse is reporting that, despite Benedict Cumberbatch denying he'll play a role in Avengers: Doomsday—he initially confirmed he'd appear—the British actor shot "pivotal, high-security scenes" under a codename. According to John Campea, that was "Ivan."
Is Doctor Strange a villain now? Not necessarily. In Jonathan Hickman's Secret Wars comic, with Earth-616 destroyed, the Avenger became the Sheriff of Agamotto and faithfully served God Emperor Doom. Battleworld was all that remained, so it made sense for Strange to protect what was left of the Multiverse, even with Doom calling the shots.
However, when his old friends returned after stowing away on a liferaft, Strange did the right thing and paid with his life at Doom's hands.
In the MCU, it seems likely that Strange has either been corrupted or, somewhere along the line, decided that Doom's mission was the best way to protect the dying Multiverse. Hopefully, we'll get some flashbacks to explain this, especially as there was a time when it looked like a Doctor Strange movie might be used to bridge the gap between Avengers: Doomsday and Avengers: Secret Wars.
We also can't discount the possibility that this is a Strange Variant, especially as Doctor Strange in the Multiverse of Madness established that they all share the same face and are a frequent danger to their respective realities.
Whatever the case may be, Strange's unmasking as one of Doom's followers is likely one of Avengers: Doomsday's biggest reveals...
Avengers: Doomsday officially stars Chris Evans, Chris Hemsworth, Anthony Mackie, Winston Duke, Tom Hiddleston, Sebastian Stan, Letitia Wright, Paul Rudd, and Robert Downey Jr. Wyatt Russell, Simu Liu, Tenoch Huerta Mejia, Mabel Cadena, Florence Pugh, Danny Ramirez, David Harbour, Hannah John-Kamen, Lewis Pullman, and India Rose Hemsworth all make their Avengers franchise debuts.
The Fantastic Four: First Steps leads Pedro Pascal, Vanessa Kirby, Ebon Moss-Bachrach, and Joseph Quinn join them, as do X-Men franchise stars Kelsey Grammer, Patrick Stewart, Ian McKellen, Alan Cumming, Rebecca Romijn, James Marsden, with Deadpool & Wolverine star Channing Tatum. The trades have pointed to Ryan Reynolds and Hayley Atwell also appearing in Avengers: Doomsday.
The Russo Brothers direct Avengers: Doomsday and Avengers: Secret Wars from a screenplay by Stephen McFeely, with whom they previously collaborated on the Avengers and Captain America franchises. Loki and Doctor Strange in the Multiverse of Madness's Michael Waldron has also been enlisted to help.
Avengers: Doomsday is set to be released on December 18, with Avengers: Secret Wars scheduled to arrive on December 17, 2027.