Terranean

Aliens are attacking Earth. You control a rocket armed with bullets and flash bombs, and are tasked with the destruction of the xeno-biological menace.

Each level consists of three waves of aliens with slightly different movement patterns. While these will occasionally fire towards the Earth, these attacks are ineffective since the planet is protected by three layers of shielding. They are more of a danger to your rocket, which they can destroy by collision or with missiles, as you move back and forth along the bottom of the screen. The aliens can be shot down with a single blast of your weapon. You also have a limited supply of flash bombs. After launch, these can be remotely detonated causing bomb fragments to fly across the screen, killing aliens in their path.

Occasionally, a mystery alien will appear. If these are not shot quickly, they will eventually remove one of Earth's defensive barriers. Once all of the barriers are removed, the planet will be destroyed. Just before all of the level's enemies are killed off, a group of these mystery aliens will appear with a small number of guards. Destroying these will complete the level. A bonus score will be given for each layer of shield remaining around the planet, and the next level (seemingly identical to the previous level) will begin. Play continues until you have lost all of your lives.