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The Triangle Key (Japanese: さんかくのカギ) is an item in Densetsu no Starfy 2. It is found in Lobber's Cave (Stage 1-4). It is found past a door that requires the Circle Key to open. The Triangle Key is one of three keys required to remove the three different types of keyholes found in the area and get to the boss battle with Konk and Puchi Ogura #1. The other two are the Circle Key and the Square Key. The Triangle Key removes all of the blue triangle keyholes.