You fire lasers to shoot down enemies, and have an ammo bar that diminishes as you shoot but recharges over time. You start with 3 health and 3 lives, and the game ends when you run out of both.

Enemies spawn on timed intervals and maneuver themselves a good distance away from you, attacking with various weapons such as lasers, homing orbs, or exploding bombs.

You must also dodge asteroids or shoot them down. Large asteroids split into pieces, which can also destroy enemies.

There are powerups that give you a temporary ability, such as rapid fire, invulnerability, or a giant laser beam.

There are various planets, stars, nebulas, and other celestial bodies that are chosen randomly and scroll by in the background.

Levels are completed when either enough time passes, or after the object in the background moves off-screen. Subsequent levels increase in difficulty and introduce new enemy types.

Your high scores are saved to an in-game scoreboard.