this game is exactly what I was expecting for a PSN downloadable game. It's fun, retro, fast paced and challenging. I still didn't had the opportunity to try it, but co-op looks extremely fun. And before I forget to mention: the soundtrack by Anamanaguchi is really good and fits perfectly in the game. The only negative I can found is that the game got a little too easy when you reach max level, even on "Supreme Master". If you're a fan of the Scott Pilgrim or old-school brawlers, this is the most fun you can get for 10 dollars.
