River Fighter - Z21 is a real time 3D fihgting game. River Fighter - Z21 is a boat that has 2 guns to fight with the enemy boats. There are 2 indicators to show the power of your boat and the score. You loose your power whenever you hit by the bulltets from the enemy boats. There are some locations where you could recharge your power back. If you destroy few boats and go further, you will see signs that indicate where to charge your power back. Once you charge the power, the power supplier will disappear and appear again after few moments, so you can always go back to same locations to charge the power. This means, if you are smart, you can play longer and get more points.