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In Spider-Man: Homecoming, Ryan Reynolds makes a brief appearance as Deadpool, breaking the fourth wall by humorously acknowledging that he is, in fact, Deadpool and not Spider-Man. This cameo is significant as it marks the first time Deadpool, a character from Fox's X-Men film series, appears in a Marvel Cinematic Universe film produced by Disney, hinting at the possibility of future crossovers between the two franchises.