Shoot the ragdoll with the cannon to hit the mark with the least amount of shots possible. Between the cannon and the target you'll find several obstacles, you have to move them to reach the end. The game includes 25 extra difficult levels.
Move the mouse pointer to aim (if the mouse pointer is away the shot will be stronger; and the direction depends on its position). When you hit the mark, a 'next level' tinkling poster will be visible on top: click on it to continue.