Space Armada (1981)

Space Armada is a clone of the game Space Invaders. Rows of bomb dropping aliens are invading your home planet, and you need to protect it! You control a laser gun at the bottom of the screen; your goal is to earn as many points as possible by destroying the waves of attacking aliens at the top of the screen. The aliens march steadily downward, and if they reach the ground or you run out of laser guns, the game is over. When all aliens in a wave are destroyed, you move on to the next, more challenging round. From time to time, a flying saucer will pass by at the top of the screen which can be shot for bonus points.