Dragon Quest Monsters
A prequel, "Dragon Warrior Monsters" ("Dragon Quest Monsters: Terry's Wonderland" in Japan), was released in 1998. This game featured Terry and Milly years before the events of "Dragon Quest VI". It was released in North America the next year, even though "Dragon Quest VI" was never released in North America. Along with Terry and Milly, several of the main enemies, including Mortamor, reappear. Their previous roles have been eliminated, however, making them appear as just normal enemies. Mortamor and Murdaw (DeathMore and Mudou, respectively, in the localization) do appear as very challenging, very late in-game bosses, though.