Dark Planet

You thrust and fire like Asteroids, but you can also "laser" the enemies on the level below you -- kind of like bombing them. When you hold down the laser button, impacts or explosions appear on the level below you, destroying any enemies they touch. There is a cannon-type gun that rolls on tracks on the ground that shoots up at you. There is also a volcano in the lower right quarter that occasionally erupts into the upper level. When you fire, your shots hit the sides of the terrain and you can bump into the top of the volcano. You can get down to the lower level of game play by entering a tube in the upper right quarter.