Air Destroyer - The Rules
You control the ship in the lower part of the screen, using as control keys: left arrow - left, right arrow - right, B - fire. The purpose is to destroy all enemy ships, without getting shot by them. The color of enemy shields indicates their shield: red stands for the most weak shield, and black for the most powerful one. As the ships are shot, their shield color will turn towards red; in this state, a bullet is enough to destroy the ship.
Your ship needs fuel, and firing at enemy ships needs energy. Both of those translate into points; you consume a small amount of points every second, and each one of your bullets costs points as well. When you destroy an enemy ship, you receive a relatively large amount of points which allows you to 'go on'. When you are hit by an enemy, your points are lowered. The game ends when you reach 0 points, or when you destroy all the enemies (by advancing to the next level).
Good luck!
Air Destroyer Product
Air Destroyer Product Page - the complete downloadable version of the game.