I quite enjoyed the book, but I agree about the ending. Can't quite put my finger on what it was that bothered me about it, aside from the fact that once Borlú is recruited by Breach, the aura of metaphysical dread surrounding them disperses a bit, to be replaced by - I'm not sure what. There was definitely some hand-waving in there, but it was hand-waving I wanted to believe in and had anticipated, so that wasn't it, or at least not entirely.