@Schradinger: I like, and it makes sense. I would rather, however, for souls attached to humans to appear in color since they are unique to humans, it would also allow him to distinguish a person from the magic they are casting. But where magic is present/ not present could be monochrome. And the haze is a good factor. I just thought not allowing a sort of distance limit would be a bit OP, but since you're suggesting it I like it. (The only reason I attached it to a sense was to impose a distance limit, and also since energy of any sort operate via vibrations, I figured tying it to his hearing, which directly receives and translates vibrations, would make some sort of sense xD to me at any rate)

@Ichthys: No worries :P I was just wondering.