Starbase Fighter is a top-down side-scrolling space fighter for the Atari 8-bit system
The player controls a small spaceship that can move in all directions, and fires straight forwards. The player starts within their home starbase, and must blast into space to seek out the enemy city. Deep in space, they must avoid attacks from alien vessels and dangerous asteroids. Numerous small alien outposts can be destroyed for bonus points. After encountering the enemy city, the player can fly inside to enter a side-scrolling stage where they must avoid enemy turrets and ships that attack from behind. After reaching the end of the city, the player encounters the Brain, which hides behind an energy wall that requires repeated hits to destroy. With the Brain destroyed, the enemy city is destroyed, and the player is free to destroy more aliens.
There are 3 levels of difficulty, and the player can choose to start with 3, 5, or 7 ships. The ship hols 99 torpedoes, but can be replenished by returning to the home base. It is game over when all ships are lost.