Hannyabal is a fictional character in the anime and manga series One Piece, created by Eiichiro Oda. He is the Vice Warden of Impel Down, the infamous underwater prison in the world of One Piece. Known for his ambition to become the Chief Warden, Hannyabal takes his duties seriously and is often seen enforcing the prison's strict rules. Despite his initial antagonistic role, his determination and unique sense of justice make him a notable and sometimes comedic presence in the series.