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The Circle Key (Japanese: まるのカギ) in an item in Densetsu no Starfy 2. It is found in Lobber's Cave (Stage 1-4). It 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 Triangle Key and the Square Key. The Circle Key removes all of the red circle keyholes.