Kamesennin/Muten-Roshi
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Kamesennin/Muten-Roshi
Kamesennin is known as the Turtle Master/Hermit/Elder.
Little is known about Kamesennin's past. It is known, though, that his master was Mutaito-sama. His fellow pupil and main rival was Tsurusennin (the Crane Master).
Kamesennin's master battled an evil entity known as Piccolo. Using a powerful wind spell, Mutaito-sama was able to imprison Piccolo within a rice pot. Unfortunately, the cost of the spell was the user's life.
At a later point in his life, Kamesennin fought with Karin-sama (the Cat Master, a large and fat cat) on Karin-To (the Karin Tower). It took him 3 years to finally be able to obtain a magic water from Karin-sama. Turned out that it was just plain water and that it was the fighting that made the potential drinker stronger.
Kamesennin has had at least two previous students, before Son Goku and his friends. They were Son Gohan and Gyuu-Maou (the Demon Bull King). If Kamesennin ever had other previous students, they are either dead, unknown, or not worth mentioning.
Kamesennin was the second of Son Goku's many teachers. Kamesennin also trained Kuririn, Goku's friend, after he left his temple.
It was from Kamesennin that Goku learned his famous Kamehame-Ha. Kamesennin said that it took him 50 years to learn the technique, but Goku learned it after just watching it being performed by the Kamesennin. Shortly afterwards, several other people are also able to use the technique. So... either Kamesennin had to develop the technique himself (which would account for the long period of time), or Kamesennin was a slow learner (maybe he was too busy watching girls), or he was simply exaggerating the time it took him to learn the technique so that it would appear to be a great move.
Kamesennin resides in his home (Kame House) on a small island in the middle of the ocean. With him is his friend Umigame (a sea-turtle). He has been known to use a small Gamera as transportation. Of course, it has its drawbacks.