Alpha Blaster

In Alpha Blaster, a derivative of Galaxian (1979), the player defends against an alien invasion fleet from the planet Alpha. Piloting a lone Federation battle cruiser, the player scores points by shooting flying saucers and other spacecraft with a laser cannon. The craft's laser energy and fuel are limited. After surviving two waves of attacks, the player must then dodge and blast through debris as the cruiser flies through an asteroid belt.

If the player passes through the asteroid belt, the cruiser docks with a supply ship to rearm and refuel. After each such cycle, the game's difficulty level increases.