DESC: When the planet Nebula was attacked by the Lone Star System 18 years ago, the few survivors vowed to protect the planet's remains with their lives. The time has come to put that promise to the test, as the mothership of the Lone Star System's armada is docking in a spaceport on Nebula. As Federation ace, Ryder Jupiter, you must defeat the Emperor of Lone and restore peace to your planet. The faithful Diana Rean will aid you pilot the Thunder Force II into battle against your foes. Only the most sophisticated use of Nebula's limited resources will destroy the craft--Are you brave enough to defend an entire planet? If your courage and weapons aren't enough, then Nebula will be crushed forever.