Sylvester Stallone is in The Suicide Squad, as confirmed by James Gunn on Twitter (below). Stallone also appeared in Gunn’s second MCU entry Guardians of the Galaxy 2. That’s it, that’s the story.

Photo from Marvel Wiki-Fandom
Sylvester Stallone is in The Suicide Squad, as confirmed by James Gunn on Twitter (below). Stallone also appeared in Gunn’s second MCU entry Guardians of the Galaxy 2. That’s it, that’s the story.
Photo from Marvel Wiki-Fandom