The Nameless One. Never has there been a character better-developed, more nuanced, and more malleable without ever deviating from the tone or direction of the characters. He encompasses so many aspects of humanity and can interpreted in so many fascinating ways. Namely, how he handles his previous actions, incarnations, and what he ultimately does when faced with the weight of these.

So yeah, Planescape: Torment probably would have at least five of these characters.