Crow could have been use to exterminate Noah, and to search for them too, since they are perfectly disguised. If so, they do their job rather terribly.... I still don't see it being really possible. They should possess god level spels to do that, taking into account Noahs special powers. Cross was defeated, but he had a dissadvantage at that battle, for he could not be the one to begin it, since he did nto know whether the one entering the room is friend of foe. And for a pro to kill just by one shot shoudl not be a problem. And Noahs are usually teh ones attaking from the shadows, not otehrwise.