Which 1986 game introduced the role-playing series Dragon Quest?

Dragon Quest introduced the Dragon Quest role-playing game series in 1986.

Enix released the game in Japan on May 27, 1986, for the Nintendo Family Computer. Yuji Horii directed and designed it, Akira Toriyama created the character and monster artwork, and Koichi Sugiyama composed the music. The game combined straightforward menu-based battles with exploration, towns, equipment, spells, and a central quest to defeat the Dragonlord.

The title was originally released as Dragon Warrior in North America because of a trademark conflict involving the name Dragon Quest. The first four North American games therefore used the Dragon Warrior name, while later releases adopted the Japanese title worldwide.

Dragon Quest helped define console role-playing conventions in Japan and became a major influence on later Japanese RPGs. Its success also established a long-running series whose numbered entries continue to use familiar character designs, monsters, and musical themes.