Leonardo of the Teenage Mutant Ninja Turtles – the one with the swords and samurai ethos. This is the earliest take on the character, from the original indie comics.
Writeups.org is an encyclopaedia of characters in genre fiction — super-hero comic books, video games, action movies, etc. It offers illustrated, researched profiles. These also include technical data for role-players. If you need a robust understanding of a character’s abilities, personality, history, etc. this is *the* place to be.