Cannon shell fire. Aim cannon, set shell speed then fire. Upon firing, the enemy will start travelling towards the cannon. You must hit the enemy before the cannon is rammed by the enemy vehicle, which doesn't have fire power. If you miss the target, adjust angle and speed then fire again before the cannon is rammed. You cannot fire another shell not until the shell hits the ground or the enemy; the enemy can start off screen in which case you are making a blind shot. Shell trajectory is governed by regular physics: initial shell speed, angle of fire and gravity, neglecting wind effect. Speed and angle controls can be set by either touching or sliding fingers in the respective control areas. You fire by touching the cannon. Randomly the enemy activates evasion mechanism, in which case you must approach the target from a high angle, putting the shell in the enemy's radar blind spot. Hitting the enemy wins a point and ramming the cannon loses a point. To win the game you must reach 10 points with a set of 150 shells.