Fido is a 1 or 2 player arcade game for the Apple II.

Your faithful companion FIDO has been mistaken for "Butch Brawler" K-9 killer. He has been taken for questioning by police GUARD robots. Because of a fatal error in the robot's Z-80 microprocessor , the robots have not only mistaken FIDO for a ruthless killer, but will get caught in a dismembering crowd control subroutine set to execute at midnight. Your mission is to fight your way through Z-80 controlled computer police weaponry to the execution station and beam FIDO to your WARRIOR ship.

The player controls a small tank which can be moved in all directions, and must be positioned on the screen before each level begins. The player combats timed rounds against a number of different opponents, and their vehicle fires horizontally or vertically depending upon the level. Each level consists of a large swarm of identical enemy vessels with very different movement schemes, and if the player is hit, they lose a life, and the timer restarts. The player starts with 5 lives, and when all are lost, it's game over.