It's not co-op. It's basically a 1+1/2 player game. Who ever plays bowser jr is just gonna sit there and press Y every now and again. The camera is god awful, especially during the giga fights. The camera will stop turning at one point and you have to stop moving to continue turning it. In the middle of a fight, standing still isn't wise. It also takes me away from the experience when I'm just enjoying the music, collecting cat shines, and then Bowser comes up again (didn't I just beat you? Didn't you go down at least 3 minutes ago?) They don't teach you how to do anything, especially with the giga bell fights. The second you grab the bell,he hits you and it's back to normal mario, which again, takes you away from the experience.