Doomsday? A cryptic post has fans buzzing, but his addition could create problems for Marvel. Find out what challenges a PG-13-rated Avengers movie could face with Deadpool in the mix.

A cryptic new Instagram post from Ryan Reynolds has fans speculating that the actor could be returning as Deadpool in "Avengers: Doomsday."

Did Ryan Reynolds just confirm his next Deadpool appearance in the MCU? The actor loves a tease and shared a particularly tease-y photo on social media that has many Marvel fans speculating whether he will return as the Merc with a Mouth in next year's event film, Avengers: Doomsday.