There will be a movie called Dark Universe, featuring Justice League Dark. And it will be 5 members. I think Lucifer Morningstar should be the main villain for that movie. I think it will be fun to see them fighting Lucifer. He's actually powerful because his powers include reality warping, nigh omniscience and immortality. Those are his powers in the comics. Let's see the DCEU version of Lucifer. But I don't know for sure who is the main villain for that movie.This is just my idea.