You are the Captain of the good ship Thundercross but problems are arising with the thrusters and power. No matter how much you use them, the ship seems to be pulled by a strange force. You realise in the area is a huge ship pulling you towards it. To add more problems, the ship has sent out various smaller crafts to destroy you. The only course of action is to confront the giant ship and blow it up. You must avoid and kill the smaller crafts attacking you before flying over the surface of the ship and destroy as much of it as you can. After a run over the surface you must face the smaller crafts again before flying over the surface of a different part of the ship. The crafts fire missiles at you and on the ship itself there are various defenses that fire as well. One touch by a craft, part of the ship or any bullet means your shield gauge decrease. Once it's empty it is game over.

Thundercross is a horizontal scrolling shoot-em-up viewed from above with the screen scrolling constantly. You move your ship with the joystick but it won't fire while you move. To fire you have to hold down the fire button and move the joystick. The ship won't move when the fire button is held.