Marvel has officially declared that The Avengers 2 will hit theatres on May 1, 2015, and Joss Whedon will be back to write and direct. That means it’s time for rumours about the new bad guy to start pouring in.

Vin Diesel recently posted a picture of the villainous Marvel cyborg Vision on his Facebook page, leading to speculation that he might play the character in the next film. The image has since been removed, but this isn’t the first time Vision has come up as a potential Avengers 2 antagonist. MTV ran an opinion piece back in May stating that co-star Clark Gregg should appear as the character. There’s been no official word from Marvel on the matter, and keep in mind that these are likely nothing more than rumours.

One thing that fans can be sure of is that the secret villain Thanos, revealed at the very end of The Avengers, will appear in the sequel. Joss Whedon says that he’s his favourite Marvel evil doer, so he may also show up in other upcoming movies like Thor: The Dark World and Guardians of the Galaxy.