Bayan

Bayan is a character that appears in the second TV special and is the main villain of the special. His only named subordinate is his second-in-command, Zap.

History
Bayan is also the main pirate after the treasure Amanda's father, whom he once knew and subsequently killed, left for her and her siblings. Bayan could control people's actions by having his pirate crew sing a song in chorus fashion which is how he got Amanda to reveal the treasure map etched on her back and Monkey D. Luffy to attack his own ship. His plan is thwarted, however, when Usopp shoots sleeping pellets into his crew's mouths while they're singing, knocking them out. When he goes to find out what happened, Bayan finds himself on receiving end of a Straw Hat seven-way group attack.

Trivia

 * Bayan is a type of chromatic button accordion.