"Simply put, this is a very short game but addictive game. You've got 3 zones to play, but what will bring you back for more are the unlockables. If you're looking for a game with a good story and depth, then this game is not for you. If you're looking for quick mindless shooting, then this game is it. And now that we've seen what SEGA can do with old arcade classics like these, I'm already itching for them to give us House of the Dead"