Robodemons tells the tale of Kull, demon king of the Hades underworld. Kull conquered the earth by using a special machine to transplant demon souls into robots. You are a brave warrior who has accepted the challenge of rectifying this situation. Using only a boomerang for offense, the hero descends into the depths of the underworld. The game begins with a flying/shooting side scrolling level and then proceeds to walking/jumping side scrolling action. All kinds of undead creatures (mostly skeletons) are waiting to destroy you.
Audibly, the game makes liberal use of digitized voices, a rarity for 8-bit NES games.