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The Legendary Bass (Japanese: でんせつのベース) is one of the three Legendary Instruments in Densetsu no Starfy 3, found in Gabun Ocean Trench (Stage 7-3). The Legendary Instruments are used for the Legendary Band that Starfy, Starly, Moe and Wotsaruto hope will put Gabun to sleep. The other two Legendary Instruments are the Legendary Guitar and the Legendary Drums. Starly finds it in map 5 (the room with Gekyojii) hidden inside some rocks.
"This Bass used to be Master Croak’s way of life! The strings on it are rusty and need to be replaced."