Destroy your enemy's castles using their own cannonballs! Move around using the A and D keys, and position yourself under a cannonball to catch it. Move the mouse around to aim, and hold down for power. Once you release the cannonball will go flying at the castle. Stone blocks need 5 strikes to break, while steal blocks can't break, they can only be moved around. If a cannonball hits you without you catching it, you'll lose one of your four lives. Once you've toppled the tower, you win the level. The less cannonballs you use, the more points you get.