Mystery Dungeon (Japanese: 不思議のダンジョン, Hepburn: Fushigi no Dungeon) is a series of roguelike video games. Most of the titles were developed by Chunsoft; other titles were developed by different companies with permission from Chunsoft to use the trademark. Koichi Nakamura, founder of Chunsoft and co-creator of the Dragon Quest series, conceived the Mystery Dungeon series as Chunsoft's first original work, basing the design on the game Rogue. Most Mystery Dungeon games center on exploring a dungeon with randomly generated layouts and fighting other characters in those dungeons in a turn-based manner; every time the player performs an action, such as attacking or walking, the opponents also take action.