Originally released in 1984 for the MZ-1500. From MobyGames: Demon Crystal is an action puzzle game. Scattered around the stage are numerous keys which help open locked areas. The goal is to find the big key which is needed to open the exit and advance to the next stage. Ares' only weapon is a limited number of bombs, which explode in a flame and can kill multiple enemies at once. The game consists of 30 stages (houses).