Splinter is a fictional character from the Teenage Mutant Ninja Turtles franchise. He is often depicted as a wise and skilled martial artist who serves as a mentor and father figure to the four turtles: Leonardo, Michelangelo, Donatello, and Raphael. Splinter is usually portrayed as a humanoid rat, having gained his intelligence and abilities through exposure to mutagen. In various adaptations, Splinter's backstory varies, but he is commonly shown as a former human named Hamato Yoshi, who transformed after coming into contact with the same mutagen that affected the turtles. His primary role is to train the turtles in ninjutsu and guide them in their fight against villains like Shredder and the Foot Clan.