Use the arrows on your keyboard to move and turn. Use W, A, S, D buttons on the keyboard to fire. Use 2 buttons at once to fire in a 45 degree angle.
You can hold down arrow keys when moving or firing. Hit P for pause and M for mute. Collect powerups for better weapons. Different powerups include: Extra Life, Bomb (destroy everything on the screen), Shield, Faster rate of fire, larger bullets (for more damage), longer range, & more bullets with each shot. Each round there are more and faster enemies.
Scoring: Each enemy ship is worth a different value and that value increases every level.
Minimum High Score: 500 - required to qualify for a high score.
Strategy: Enemies that can dodge bullets are very hard to hit at long range. Try keeping them at bay with your weapons and search for more powerups. When you see a Bomb (B) powerup, you may want to save it until the enemies respawn.
Note: If the games starts slowing down, some graphics and sounds will be removed to try to speed it back up. You might notice that stars start disappearing, or the explosions aren't as big, or even the image quality seems to decrease if the game slows down due to too many enemies on the screen. Nothing that affects game play will change.