Dark Kingdom lets you experience a traditional story of a Japanese RPG from “the other side”. In this game, you play the role of a mercenary named Gene Dorman. Instead of becoming a world-saving paladin, Gene joins forces with the Demon King himself! He offers his services to him and receives from him various assignments. Gene doesn’t yet know that fate will make his path cross with that of the “good” hero Lux, with whom he shares a mysterious connection…
Gene must complete the missions of the Demon King in a specified order, and each time he completes a mission, his rank raises, allowing him access to higher levels of the hierarchy of the Demon King Castle, new abilities, etc. Other servants of the Demon King join him on his mission, and fight together with him as a party. The battles are turn-based and are viewed from first-person perspective. The game has an internal clock with day and night cycle.