Jack Hanma is a fictional character from the manga and anime series Baki the Grappler. He is known for his immense strength and muscular physique, which he developed through rigorous training and a desire to surpass his father, Baki Hanma. Jack is often portrayed as a fierce fighter with a relentless determination to prove himself in the world of martial arts. In the series, Jack Hanma is characterized by his unique fighting style and his ability to adapt to various opponents. His backstory includes a troubled childhood and a complicated relationship with his family, particularly with his father. Jack's journey in the series highlights themes of rivalry, ambition, and the pursuit of power.