Demon Attack

Demon Attack was Imagic's most popular Atari 2600 game, and was ported over to just about every major platform in the early 1980's. It was a basic space shoot 'em up, with some innovative effects for the time (the demons "implode" onto the screen). In later levels, demons shoot lasers, and hitting demons will split them into smaller ones. There is also a large mothership to attack, similar to the last stage of the arcade game Phoenix (or the Coco version Demon Seed). For each wave, the demon's change in appearance, too.