In Star Fortress, our task is to blast holes through the multi-layer shielding above you to get to the the enemy ship behind. Avoid the orbs raining down upon you from above. Once there is a clear path through the shielding, the enemy ship will fire laser bolts at you, too. As each level progresses, the enemy ship will require more direct hits to be destroyed. Also, the number of layers of shielding will increase. With every direct hit, the enemy ship will move slightly faster.

You can use either the keyboard or the joystick to control your ship. With the joystick, push or to move in the corresponding direction and press to fire your weapons. You can also hold down for rapid fire. If you're using the keyboard, press T and U to move LEFT and RIGHT. Fire with either the , keys or . Pause the game with either or and quit the game with + .

You can change the level at which you start the game on the introduction screen. The higher the starting level, the higher the bonus points at the end of each level completed.