Aliens

Aliens is a fixed screen shoot 'em up. Like other games of its kind the player controls a space craft that can be moved left and right along the bottom of the screen. The abstractly shaped aliens appear from the top of the screen and descend towards the player who has to shoot them before they reach the bottom. The aliens move vertically in a straight line and when reaching the bottom the player is instantly killed. The player only has one life and has to restart the game when getting killed. Killing 25 aliens leads to a new level with another kind of aliens. In total there are sixteen levels.