Space Invaders Part Four

Space Invaders Part Four © 1979.

In this pirate version of Space Invaders:
1) The saucers that run across the top of the screen shoot back at you when they have a clear shot.
2) Some invaders split into two invaders on either side of the original, giving you more invaders to shoot.
3) When you finish a rack, the following gets printed on the screen: "Well Done Earthing, this time you win. Now do battle with our super forces.".