Originally Posted by The Man
You can't accuse him of being "one-dimensional" if he has a clearly delineated motivation and rationale; a "two-dimensional character," possibly, but "one-dimensional character" refers specifically to characters who are solely there to move the plot along and have no clearly delineated motivations or rationales of their own. I will not argue the point that there are many characters like him in other games, but that alone does not make him a one-dimensional character, any more than it makes Kain or Shadow or Vincent a one-dimensional character.