Marsyas is a character, (a satyr, to be precise), from Greek mythology who was a follower of the goddess Cybele and is best known for competing in a musical contest against the god Apollo.
The myth surrounding Marsyas begins with the goddess Athena and her creation of a double flute, made from the bones of a stag. Athena played beautiful music on her flute at a banquet in Phyrgia attended by the other gods of Olympus. Everything seemed to be going well and her music was well received but she happened to notice that two goddesses, (Aphrodite and Hera), were poking fun at her as she played.
Leaving the banquet and entering the surrounding forest, she sat down by a stream and began, once again, to play. At this point, Athena caught site of her own reflection and was horrified to see how her face contorted whilst playing the flute. She threw the newly-invented instrument to the ground and placed a curse on whoever picked it up
Marsyas found Atherna's flute, picked it up and put it to his lips. Wonderful music emanated from the flute, although it is not clear whether it was Marsyas' previously-undiscovered innate music ability or the lingering magic of Athena that caused the flute to emit such tunes. Enthused by his discovery, Marsyas took his flute and walked through the streets of Phyrgia, where everyone who heard his music was delighted and greatly entertained. Some said that even the god of music himself, Apollo, could not have played better.
Apollo was furious when he heard about this, and set forth to defend his musical reputation. He sought out Marsyas and challenged him to a musical duel. Naturally, the Muses would act as judges. The winner of the contest would be allowed to inflict whatever punishment he saw fit on the other.
Marsyas rose to the challenge and played a wonderful tune on his flute. Apollo replied with a piece played on his lyre which the Muses also found hard to fault. They declared the contest a draw. Acting quickly, Apollo proposed a second round of competition, with some new conditions: each contestant would play his instrument upside down and sing at the same time. Marsyas fell for this trick and subsequently lost as he was unable to fulfill either of the new conditions. Apollo chose to punish him for his arrogance by flaying Marsyas alive and hanging his skin from a tree as an example to others who might challenge the gods. The river Marsyas was said to have formed from his blood and the tears of his satyr companions.
Moral: Excessive pride will always be punished by the gods.