ZX Asteroids is based on the arcade game where you are a craft sitting in the middle of the screen surrounded by large asteroids moving about the screen. You have to blast all the asteroids, and when one is shot then it splits into smaller asteroids and keeps repeating the process until the asteroid has gone. You can turn your craft left or right 360 degrees but you can also move forwards. Occasionally an alien craft will appear and when shot gives you bonus points. If you are hit by an asteroid or the alien craft then you lose one of three lives. Two players can play and each player takes it in turns when the other player loses a life and there are five levels of play (1-5) with one being the easiest.