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Zelda: Skyward Sword has an overworld underworld complex - Infendo: Nintendo News, Review, Blog, and Podcast
As producer Eiji Aonuma explains it: “Traditionally a dungeon is a place where it’s all about combat and going from room to room, defeating enemies to get to the end. In Zelda: Skyward Sword, we’re trying to move the small connected dungeon rooms into an area that might traditionally be considered a field or overworld. We’re thinking about creating dungeons where you don’t have a sword and your goal is not to defeat them confronting enemies, but to circumvent them or run away from them to clear that particular dungeon. That’s one way the structure of Skyward Sword is different from other Zelda titles.”