Sphere of Influence

Sphere of Influence is a 1-player arcade game for the Apple II.

The player controls a small spaceship on the bottom of the screen which moves horizontally and fires vertically forwards. A large ball drops from the top of screen, and the player attempts to shoot off pieces of it without being hit by the descending object. After the object passes through the bottom of the screen, it appears again at the top. If the entire ball is destroyed, the player advances to another identical level. The player starts with 3 ships, and it's game over when all are lost.