Literature
Seth's Bio
Although the son of the known hothead, Raphael, he is much more like his uncle, Leonardo. Seth was the first born mutant in the family, his parents being Raphael and Eve. Being Eve was originally human, he has part human and part mutant turtle DNA.
Leonardo took Seth mostly under his wing and immediately started training him up in ninjitsu and training him to one day lead as well. Seth followed after his uncle Leo passionately, and was a natural fighter.
It didn't take long for him to find other passions. One particular passion he picked up from Donatello was engineering. Seth excelled in his lessons on fixing things, especially vehicles.