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Herman's Shell (Japanese: ヤドカリタのかいがら, Yadokarita's Shell) is an item in Densetsu no Starfy 4. It is found in Stage 1-2 (Lobber's Villa). It is a blue bag containing Herman's belongings, including one of Herman's shells for 'everyday wear'.
In the story, Herman asks Starfy to locate it and punish Fork, promising Starfy with Treasure. When Starfy and others return it to Herman, he puts on a golden shell from the bag. Starfy and Starly apparently weren't expecting Herman's Shell to look the way it does, and look weirded out.
As a reward for returning Herman's Shell, Herman rewards the player with the Herman Hat treasure.