This shoot-'em-up will give you an aching fire digit on your first play because it's more a war of attrition than a quick zap. You are as ever defending your planet but this time you are protecting a shield below your base from being holed.
At the top of the screen is an indestructible mothership while whizzing around the middle are hordes of diving ships. These release two sorts of missiles that try to penetrate your defences. If a hole in the shield gets large enough, a diving ship will enter it and turn into a mothership.
The motherships also release glowing pods which if allowed to reach the shield mutate into red aliens. They can only be stopped by digging a hole in your own defences. Attack ships also appear to bombard the defences but once there are enough motherships, they start to descend the screen and try to crash into you.
Good News
P. Constant pressure from alien ships.
P. Colourful, fast-moving graphics.