Destroy all the bubbles in each level with your harpoon gun. Bubbles divide into two smaller bubbles when hit by your harpoon. When the bubbles are in their smallest form, you can shoot them to make them disappear. Collect power-ups that fall from the bubbles.

Player 1 uses left/right arrow keys to move and space bar to shoot. If selected, player 2 uses 'X' and 'Z' keys to move and 'W' to shoot.