Shoot balls and various other floating/bouncing objects with your gun to clear levels. Travel across Europe in tour mode or compete in panic mode. Very addictive but can be frustratingly hard. Best with a friend in two-player mode.
If you hold down on the joystick while playing in panic mode, 500 points will be added to your score every few seconds. This should help you get extra men quicker but will also place you in more danger since there will be more bubbles coming onto screen. Also in panic mode, if you go without shooting anything for the amount of time it takes for the background song to repeat, you will automatically get 10000 points, but the speed of the balls with suddenly become extremely fast.
In tour mode, if you set the board for one life per game, you can easily pass all the levels by switching to player two’s side when you die as player one, and player one’s side when you die as player one. The levels will not start completely over every time you die.