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I was disappointed to see Snake walk over to the dark side for good, though. I always liked the ambiguity about his character, that he was neither thoroughly bad nor completely good - or, rather, not as bad as Harry thought he was. Or maybe I just REALLY fancy Alan Rickman as Snape and project that onto the books :) Anyway, I'm still hoping it'll prove to be a mistake and that he wasn't really responsible for Dumbledore's death.