There are numerous islands(Japanese: 島) in the main setting of Dragon Quest Characters: Torneko's Great Adventure 3 Advance: Mystery Dungeon. The main story dungeon encompasses all three islands and its surroundings, with towns and side dungeons dotted in between. Side dungeons are unlocked during the post-credits, though progress can be and should be made to unlock them during the story.
These dungeons are visited as part of the Main Story and can be revisited at any time. There are also dungeons which are available only during the Post-credits while others can be unlocked throughout the main story.
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