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The Legendary Guitar (Japanese: でんせつのギター) 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 Bass and the Legendary Drums. Starfy finds it in map 4 (the map with Gekojii) hidden inside some rocks.
"Old Man Croak’s younger years were filled to the brim with playing this Legendary Guitar! The strings on it are rusty and need to be replaced."