Viewed from above and set in space, Blastar is a multi-directionally scrolling shoot 'em up. Each of the 12 levels have aliens coming at you in all directions, and you must use the scanner to see where they are, and fly around taking them out. The ship has heavy inertia, so you can't brake and steer instantly. Contact with aliens weakens your ship, and eventually costs you one of your 3 lives.