ZX Spectrum 48K:
Space simulation as serious as "space invaders" combined with an over-the-top storyline of science fiction meets real history, provoking more questions than it even pretends to answer, Starion is one weird mess and a piece of gaming history nearly forgotten in the shadow of That Other Space Game. (No, not F.O.F.T!)
The Spectrum version is the definite one, and Amstrad is nearly identical.