The Frog's Song of Soul is one of the three melodies Link learns in The Legend of Zelda: Link's Awakening. Link learns this after paying a large sum of rupees to listen to Mamu's frog choir, who perform the song for him.
Its main purpose is to revive the Flying Rooster that was but a mere skeleton under the Mabe Village weathervane before Link returned it to life through the song's magic. It was also used to open the entrance to Turtle Rock.