Warning: Includes Doctor Strange in the Multiverse of Madness SPOILERS.
Although Deadpool doesn't appear in Doctor Strange in the Multiverse of Madness, the film actually kind of sets him up. Writer Michael Waldron confirmed that the production team actually considered adding Deadpool to the Doctor Strange 2 cast for a cameo, but it didn't quite pan out. However, Doctor Strange 2 actually perfectly paves the way for the Merc with a Mouth to finally enter the MCU.
Since the moment Disney bought Fox, viewers have been wondering how the X-Men will be integrated onto the MCU main stage. Deadpool is one of the few mutants that is confirmed to still be played by their Fox actor (Ryan Reynolds) in the MCU. Because of this, many speculated that he would show up in Doctor Strange 2, as the multiverse seems like a perfect way for these characters to cross over. While some X-Men are steadily beginning to appear in various forms — evidenced by Patrick Stewart's Professor X appearance in Doctor Strange 2 - Deadpool was sadly not in the film.
Related: Doctor Strange In The Multiverse Of Madness Easter Eggs & MCU References
Doctor Strange 2 doesn't actually set up the character of Deadpool, but it does set up a way that the MCU could handle the character and incorporate him into the universe outside of featuring in his own films. One of the biggest issues surrounding Deadpool is that he is a fairly graphic character. Both Deadpool films are R-rated, known for their profanity and extreme violence. On the other hand, the MCU is made up of mostly PG-13 projects, leading to a pretty apparent clash when trying to bring Deadpool into the universe. So far the MCU has been pretty clean, but the release of Doctor Strange 2 and other Phase 4
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