4. Prometheus
The unnamed child of two bank robbers, shot by the police. He swears on their graves to fight against the forces of law and order. He travels the world, learning information and fighting techniques. Eventually he finds an alien key that opens into limbo where he builds his base. He also constructs armour and weapons, including a helmet that can download any information into his brain. Basically as the character is an evil version of Batman, this could lead up to a final battle with them, while the rest of the League is having to save the world. Unfortunately, given the recent film by Ridley Scott, they could wind up changing his name to avoid confusion.