Solaseed

is a troubadour who joined the Great Fight Festival for an unknown purpose.

Appearance
Solaseed appears to be very short young man who wears a cap, coats, and carry around a guitar with him.

Great Fight Festival arc
After accepting the invitation to the Great Fight Festival at Vaizel, Solaseed entered the labyrinth where he later sat on top of the highest wall and sang a song with his guitar at the carnage and massacre of many participants by the mercy of the Earth Crawlers.

Trivia

 * Solaseed's guitar appears as one of the relics that Meliodas mentions when talking about the Goddess Clan residing within objects in an omake in Volume 24, hinting that there could be a Goddess residing within it.