Castle Quest is a unique blend of board strategy and magic battle confrontations. The game challenges players to defeat their opponents' king in a fantasy-themed chess-like experience. A player controls a small army, comprising of various units such as orcman, karate man, and warrior, on a small chessboard.
The gameplay involves moving units around the board, where they can engage in battles with each other or with enemy pieces when they meet on the same square. These battles take place on a special screen featuring a playing-card roulette, which determines the outcome based on the cards drawn by each unit. Units have different health points and card abilities, such as the instantly killing joker card.