Sabotage (1981)

You are in control of a stationary gun turrent at the bottom of the screen. Planes drop bombs and paratroopers jump out of helicopters which you have to shoot. Every hit gains you points - every shot you fire looses you points. You have lost if a bomb destroys your turrent, a paratrooper lands directly on your turrent or four paratroopers land at any side of your turrent. In that case they are able to build a human pyramid to infiltrate your turrent and blow it up.