Tsunade is a former student of the Third Hokage. She is also the granddaughter of the first Hokage and grandniece of the second Hokage. When asked to be the Hokage, Tsunade refused it because her brother and boyfriend Dan died in pursuit of their dreams to become Hokage. Then she lost faith in the title and the concept of dreams. But she later regains her faith in both after meeting Naruto Uzumak. Then Tsunade accepts the position of Fifth Hokage to protect Konohakagure.
Tsunade also is a talented medical ninja, and she can heal injuries that most others would consider incurable. Her healing abilities are such that she has devised a method of Mitotic regeneration for herself, making her all but invincible in battle. However, using it greatly shortens her overall lifespan.
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