There are two different play screens that alternate:
- Wave 1 uses pseudo 3D graphics and has a large red bit of what appears to be part of a very large spaceship as background on the bottom half of the screen. You can move your ship around anywhere on the red background, but the black area beyond is off limits. The game opens with a large mothership craft visible at the top of the screen, but your shots cannot reach it at this point. Red aliens quickly begin attacking you, swooping in line formations from the top area of the screen. They scale in size as they get closer to you. After the armada is gone, the mothership begins spewing out groups of red aliens, and a new green ship that fires at you. Eventually the mothership will stop spewing fighters at you, and the entire screen will scroll up, and the game will begin the second wave.
- Wave 2 pits you against the mothership directly. You will find that your multi shot is gone, and you can only have one shot on the screen at a time. The mothership has three areas that must be blasted away.