The object of the game is to avoid colliding with the asteroids and to destroy as many asteroids as possible by shooting them with missiles.
For each asteroid you destroy, your score increases by 1. If your spaceship hits an asteroid, you lose.
As time passes, the game gets more difficult. The asteroids get progressively faster and more numerous.
Use your keyboard's arrow keys to move the spaceship. Use the spacebar to shoot missiles.
Use the on-screen arrows to move the spaceship. Press the rocket icon to shoot missiles.