We now know who the villain in Doctor Strange 2 might be, in addition to some other details about the possible sequel. Marvel is currently being very cagey regarding their slate of movies following the conclusion of Phase 3 next year when Avengers 4 is released. However, it seems like Doctor Strange 2 is all but a guaranteed, even if it isn't confirmed just yet. That said, if writer C. Robert Cargill and director Scott Derrickson are invited back, they know where they're going with it.

C. Robert Cargill, who wrote Doctor Strange with Scott Derrickson, recently spoke at a Q&A following a screening of the movie in Austin, Texas. During the Q&A, Cargill spoke a bit about where they want things to go in Doctor Strange 2 and he says, "Nightmare will be the villain." Nightmare is one of the major foes of Stephen Strange in the world of Marvel Comics and, according to Cargill, he and Derrickson are committed to bringing him into the fold if they get to make the sequel.

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For those who may not be familiar with the relatively obscure rogues gallery of Doctor Strange villains, Nightmare is generally depicted as a demon and ruler of the Dream Dimension. He was introduced in Strange Tales #110 in 1963. In addition to being a generally powerful omnipotent, other-dimensional being, Nightmare has the ability to draw power from the psychic energies of the subconscious minds of dreaming beings. But what of Chiwetel Ejiofor's Mordo? Here's what Cargill had to say about it.

"Marvel movies work in threes. They also work outside of their threes. Some of the better Marvel films have more than one villain in them. Me and Scott have not laid the groundwork for it but what I can say is that I have a feeling that whatever Nightmare is involved with, Baron Mordo, being somebody who considers himself the defender of natural law will have something to do with it."

Mordo was an ally to Stephen Strange during the majority of the first Doctor Strange. However, he felt betrayed by The Ancient One and Strange, who were using forbidden powers in order to do what they felt needed to be done. As seen in the final post-credits scene in the movie, Mordo is on his way to becoming the villain that most know Mordo to be from the world of Marvel Comics. Cargill elaborated a bit, saying that Marvel Studios is playing the long game with the character, which is part of the reason Chiwetel Ejiofor was interested in playing the character in the first place.

"For those of you who have ever read the comics, you know that Baron Mordo has a very particular arc, and that's something we discussed with Chiwetel while working on the first movie. And part of the reason Chiwetel wanted to play Mordo was because he has a definitive ending as a character and it's such a fascinating ending. And I do know that whether we're attached or not, that Marvel plans on working towards that ending and fully realizing Mordo as more than just a cardboard cutout villain, but actually taking him to kind of Loki levels of awesomeness. That's the goal with him."

Any comparisons that can be made to Loki are certainly good. Granted, this is all what Cargill and Scott Derrickson would like to do. At the present time, they have not been confirmed to be returning for Doctor Strange 2, but they both want to come back. And Marvel has a history of bringing creative teams back when things go well. Doctor Strange made $677 million worldwide and currently holds an 89 percent approval rating on Rotten Tomatoes. Safe to say, things went well.

As for this Mordo arc that Cargill is talking about? There's a lot to the character in the history of the comics, but he becomes Stephen Strange's greatest foe and eventually aligns himself with Dormammu, who showed up in the first movie. However, this use of black magic eventually leaves Mordo with incurable cancer and renounces his evil ways just before his death. He eventually returns, because that's how comic books work, but this is likely the "definitive ending" Cargill is getting at.

Doctor Strange introduced some very weird stuff into the MCU, but fans seemed to dig it. Cargill also says that, should they return, they want to get more weird with it. "That's the thing. If we do another film it's going to be weirder than this one. That's the only way we'll do another one is if we get to get weird," he said. And, as he tells it, Marvel fully embraced the weird the first time around, so that shouldn't be a problem. Hopefully, Marvel brings them back so they can make this happen.