The alien commander Clomatandria controls the Clomazavendra galaxy and intends to make it the center of the universe by destroying everything else. Earth is her next target. In response, the planet's best scientists developed X-Castera — an energy shield that must be physically installed and activated at multiple locations across the world. Clomatandria's fleet has been dispatched to stop that from happening. Fighter pilots must activate X-Castera and keep it running against the incoming attack.