Nikato Kuzuraki is the original creator of the Flash Technique and Rasengan. As he found Minato, he taught him the Rasengan and the Flash Technique. He also tells him not to tell anyone except his teacher that he is alive. He is currently alive in the Uzumaki Country meditating. He is 47 years old.
Nikato Kuzuraki was a very anti-social boy, and never wanted to meet anyone. He was forced to go to the Academy, and lost very little of his anti-sociality. Once he became a genin, he became very social, and eventually developed the rasengan. During a S Rated Mission, his friend Ikata Hakuto was in trouble. Right when she was going to be killed, Nikato teleported to save her and created the Flash Technique. As a Chunin, he was at Kage level, becoming the strongest of his friends. The 3rd Hokage wanted Nikato to sucess him. Nikato chose Minato instead, and stayed as a Jonin for the rest of his life. Now he is preparing for Madara's attack. He also has the rinnegan, but wasn't activated due to Nikato's will to use his own power. He also married Ikata and had a child, Naruto Kuzuraki, named after Minato's son.