Batman v. Superman: Dawn Of Justice isn't out until next year, but director Zack Snyder is already talking about the future of the franchise. In a new interview with Entertainment Weekly, Snyder hints that Superman villain Brainiac will appear in a future Superman film.
“I remember talking about ‘What’s the next villain? We can’t do another alien invasion,’" says Snyder when asked about his original, pre-Batman plans for the Man Of Steel sequel. "Brainiac was definitely down the road. Metallo, I think, was going to be the main bad guy of this movie.” (via ComicBookMovie)
Unfortunately, outside of Lex Luthor and General Zod, Superman doesn't have many well-known villains. Brainiac sounds like the logical next step. Batman v. Superman: Dawn Of Justice releases next year, on March 25, 2016.