interesting
Orochimaru (大蛇丸), featured in the Japanese folktale Jiraiya Goketsu Monogatari, is the arch-enemy of the ninja Jiraiya. He was once named Yashagorō (夜叉五郎) and was one of Jiraiya's followers, but he was overtaken by serpent magic. Having changed his name to "Orochimaru", he gained the ability to turn himself into a giant serpent. He attacked Jiraiya and his wife Tsunade and defeated them with his venom (only for another follower to save the couple's lives afterwards).
EDIT:
Jiraiya (児雷也 - literally "young thunder"), the title character of the Japanese folktale Jiraiya Goketsu Monogatari (児雷也豪傑物語, "The tale of the gallant Jiraiya"), is a ninja who uses shapeshifting magic to morph into a gigantic toad. The heir of a powerful clan in Kyūshū of the same name, Jiraiya fell in love with Tsunade, a beautiful young princess who masters snail magic. His arch-enemy was his one-time follower, Orochimaru, who mastered in snake magic.
EDIT:
Jiraiya (児雷也 - literally "young thunder"), the title character of the Japanese folktale Jiraiya Goketsu Monogatari (児雷也豪傑物語, "The tale of the gallant Jiraiya"), is a ninja who uses shapeshifting magic to morph into a gigantic toad. The heir of a powerful clan in Kyūshū of the same name, Jiraiya fell in love with Tsunade, a beautiful young princess who masters snail magic. His arch-enemy was his one-time follower, Orochimaru, who mastered in snake magic.