Cyclon

Cyclon is a space-themed reflex shooter for the Commodore VIC-20, developed by Alan Pavlish and published by Boone Corporation. Inspired by the style of Space Zap, the game challenges you to defend a central star base from enemies approaching and firing from every direction.

Lasers can be fired in four directions, while limited anti-matter bombs destroy all enemies on screen. Shields intercept incoming shots but, like the lasers, consume energy. Damage can disable shields on affected sections of the base, and enemy fire that reaches the reactor destroys it. If energy is depleted, the base explodes.

Cyclon features 99 difficulty levels, with starting points from levels 0 through 10. You begin with three bases and earn another after completing each level. Remaining energy is converted into bonus points at the end of a round, but the game ends when all bases are lost.