Dragon Quest Monsters is a turn-based RPG that involves recruiting monsters to fight for you in random encounters. Two recruited monsters can be fused together for a better one and extra monsters can be stored on a farm while not in your party. It was released in Japan for the Game Boy Color before the system was released.

In the days before Dragon Quest VI, when Terry and Milly were just children, a strange monster appeared one night and snatched Milly away. Soon after, another monster, similar to the kidnapper, appeared and told Terry his sister was kidnapped by the evil Warubou. He informs Terry that his name is Watabou and must accompany him to the Kingdom of GreatTree.