David Braben‘s Virus (aka Zarch) is a startling 3D shooter with unique landscape movement and ship controls. Jez San and Argonaut Software did the Atari ST and Amiga conversions of Virus in 1988, and they were published by Firebird.

Your craft is controlled by using the mouse only, and the analogue movement makes for a very tricky game. One false move and you’ll flip your ship around and into the ground. Steady, measured movements are what is required to stay in the air and earn points.

The aim of the game is to blast various attack waves out of the sky, while avoiding contact with the checker board patchwork quilt that is the ground. It’s easier said than done. You also get negative points for shooting and not hitting anything!

More: Virus on Wikipedia