Muten Roshi, also known as the Turtle Hermit, is an ancient and legendary martial arts master who appears as a supporting character in Dragon Ball Z Kai. He was born more than three hundred years before the events of the series and resides on a small island called Kame House, accompanied by his anthropomorphic turtle companion Umigame. As the founder of the Turtle School, he created the iconic Kamehameha technique after decades of martial arts study. Throughout his long life, he has trained many notable fighters, including Grandpa Son Gohan, the Ox-King, Son Goku, Kuririn, and Yamcha. His physical appearance is distinctive: he is bald with a thick white mustache and beard, almost always wears sunglasses, and is often seen in beach clothes or a martial arts suit with a large turtle shell strapped to his back. He typically carries a walking stick. In terms of personality, Muten Roshi is a blend of contradictions. On one hand, he is a wise, perceptive, and benevolent mentor who possesses deep knowledge of martial arts philosophy and discipline. On the other hand, he is famously lecherous, often making comedic sexual advances toward attractive female characters such as Bulma, Launch, or Maron. This behavior serves as a recurring source of comic relief. He can also be cantankerous and whimsical, displaying a playful or foolish side, yet he consistently demonstrates genuine care and love for his students and friends. His motivations are rooted in a desire to pass on the teachings of the Turtle School, to protect the Earth from threats, and to ensure that his students grow strong enough to defend themselves and others. He believes that true martial arts strength comes not just from raw power but from discipline, daily physical effort, mental balance, and a humble attitude. This philosophy is central to his training methods, which often involve seemingly simple but grueling tasks such as delivering milk, plowing fields, and swimming with heavy shells. In the story of Dragon Ball Z Kai, Muten Roshi's role is largely that of a retired master and occasional advisor. He was once considered the strongest mortal fighter on Earth, but his power is quickly overshadowed by the arrival of Saiyans, Namekians, and other immensely powerful beings. As a result, he does not engage in major combat during the main Z arcs. Instead, he provides guidance, comic relief, and a link to the earlier adventures of Goku's childhood. His home, Kame House, serves as a gathering point for the Z Fighters. Despite his reduced combat role, he remains a respected figure and is sometimes called upon for his wisdom or to perform specific techniques. Key relationships define his place in the series. His most famous student is Son Goku, whom he first met when Goku and Bulma helped his turtle return to the sea. He later formally trained Goku alongside Kuririn, and both adopted the Turtle School symbol on their outfits. He also trained Yamcha. He has a long-standing friendship with Bulma, though he frequently harasses her. He is the older brother of the fortune-teller Baba. He also shares a rivalry with Master Shen, the head of the Crane School, which dates back to their own youth. In terms of development, Muten Roshi is a static character in many ways, but key moments reveal his depth. Early in the original Dragon Ball, he participated in the 21st World Martial Arts Tournament under the disguise Jackie Chun in order to prevent Goku and Kuririn from becoming overconfident. That fight showcased his impressive skill and forced Goku to grow. Later, during the King Piccolo saga, he demonstrated tremendous heroism by attempting to use the Mafuba, or Evil Containment Wave, to seal the demon, even though he knew the technique could cost him his life. The attempt failed and he died, though he was later revived with the Dragon Balls. This act cemented his legacy as a selfless protector. His longevity is explained by his use of a mystical herb called the Paradise Plant, which he consumes to extend his life. Muten Roshi possesses several notable abilities. His most famous technique is the Kamehameha, a concentrated wave of ki energy that he invented after decades of training. When using this attack at full power, his body undergoes a dramatic transformation, becoming massively muscular and taller, yet his speed and precision remain unaffected. In this state, his Kamehameha is powerful enough to destroy the Moon. He is also adept at the Mafuba, a sealing technique that traps evil beings in a small container, though it is extremely dangerous to the user. Additionally, he has a high degree of martial arts skill, exceptional reflexes, and a keen tactical mind that allows him to compensate for his physical decline against younger, stronger opponents. He also employs various other ki-based attacks and has the ability to increase his size and strength by focusing his energy. Overall, Muten Roshi is a foundational figure in the Dragon Ball universe whose teachings and influence resonate across generations of fighters.