I know that we're sure that a Black Dragon still retains his acid breath weapon, but the last I checked, no one knows if a Black Dragon has maintained its aquatic nature. I've been reading alot of posts about escape tunnels to water sources and things of that sort, but what if that doesnt gain the black dragon the benifits it used to? What if the black dragon's natural habitat is now within a cave. Or what if now -gasp- a black dragon is just a dragon, with no prefered geographical location?
I could be quite wrong here, but we dont know for sure yet. Do we?