Many questions surround Avengers: Doomsday, and one major one is whether Mark Ruffalo will reprise his role as Bruce Banner. The actor recently appeared in Spider-Man: Brand New Day as Banner, and the Russo Brothers teased that the Hulk is “certainly involved” in the story around Doctor Doom. “I think [what] we could say is, [Banner] is certainly involved in the story that revolves around Doom,” Joe Russo told Empire Online. “We will not confirm nor deny his appearance in Doomsday.” Anthony Russo added, “The farthest we can go is to say, there are characters and actors who have not been…