A two player game is tough on a single keyboard. Keyboard and controller or two controllers is fine. But, if you don't have another person to play with, you're SOL. I would have preferred to see more game where you take control of each character at different times for whatever reason. Or, extend that out beyond just having two players or characters, but maybe have two ways out, two possible outcomes, two paths to a target, two bosses to defeat, etc.