Spawn of Evil

The long range scanners have detected an object in space.
It is identified as an Ectogenetic Galactic Gamete (E.G.G.)
Your mission is to destroy the E.G.G ans all of its progenety.

Spawn Of Evil is a ZX spectrum game released in 1983 on tape. There are two "parts" of the game : First the search of aliens to destroy on a map and then a first person view shooter.