If you didn't get Dead Rising 2 (Main game); get Case Zero.
If you're done with the main, get Case West.
At least if you have Co-Op problem, Zero is best to get 200 (I done with it way before I got my hands on the main game) on your own. --- Yes, despite his grammar I can tell he's quite intelligent. He's also always willing to help others who play this game. I too appreciate that. ~Golden_Key33