Liberator (UK) (1989) [a1] - Amstrad CPC - Strategy, Action

Once again, Earth has been invaded by an alien army who have somehow arrived undetected – until now. Armed with an automatic machine gun, you must reach their underground control centre and destroy it. This horizontally scrolling shoot-'em-up takes place over 3 levels, and right from the start, a relentless stream of aliens will attack you from both sides. There are power-ups available so keep on firing till victory.