From the back of the box: You are the commander of the Centurion, an Earth Federation starship guarding a remote corner of the galaxy. An alien invasion fleet from the planet, Badnewsia, has penetrated the galaxy's outermost defenses! If you do not destroy it, earth will be enslaved by the enemy hordes! Disintegrate enemy invasion transports with laser blasters! Elude enemy star fighters warping in from hyperspace!