Police are seeking witnesses to a "vicious" assault at the Hokitika Wildfoods Festival, believed to have been carried out by a man dressed as a Tetris box.
The victim suffered a broken jaw, broken eye socket and cuts to his face in the March 10 assault.
He required surgery to have plates inserted into his face.
The attack happened about 6pm near toilets within the fenceline of Cass Square.
The offender was believed to be caucasian, aged about 25, and dressed as a Tetris box, from the popular video game.