Date: 1970s-1990s

Hamato Yoshi was once the leader of the Foot ninja clan in Japan. One of his students, Oroku Saki, sought to seize control and framed Yoshi for attempted murder. Disgraced and exiled, Yoshi fled to New York, where he lived in poverty among the sewers and befriended the rats. After four baby turtles were accidentally lost in the sewers, Yoshi discovered them exposed to a mysterious mutagen. The substance transformed the turtles into humanoids and turned Yoshi into a mutant rat, reflecting his last contact with rodents. Taking the name Splinter, Yoshi raised the turtles in secret, naming them Leonardo, Donatello, Raphael, and Michelangelo and training them in ninjutsu to survive in a world that would never accept them.