Skraelings: The Skraelings look like an exotic race of humans, but they are not, and spending even a few moments with one of them impresses on any race of human the utter alien-ness of the Skraelings. They are (reputedly) the descendants of Atlanteans who weren't on the island when it sank, either because they were colonials, slaves, outcasts, or some other group that was on the mainland. Who were the Atlanteans? Surely they were an early population of human, right? They look human enough; anthropomorphic shape, brown skin that's not out of the range of some populations on the mainland today, bright blue eyes, and dark brown hair. Sullen and with strange, uncouth voices and languages, yes, but weren't the Atlanteans human? Most believe that they actually were not, and in fact are as distant and strange from humanity as the kemlings, who have daemonic taint in their bloodstream. 

Skraelings mingle little with the other races, and usually only exceptional individuals or outcasts are seen outside of their tribal groups.  It's not clear why, but some few who have interacted with the Skraelings notice that they do not use any metal for any use whatsoever. Even more unusually, this does not seem to be a cultural or religious taboo; metal somehow seems to react badly to the Skraelings, and they fear its presence tremendously (not that that means that they flee from those bearing metal weapons, merely that they will leave them where they fall rather than take them themselves.)