Coldharbour, the immense realm of Molag Bal, is also one of the most inhospitable realms, consisting only of charnel houses and vast slave pens. Any mortal found here is captured and placed in one or the other. It resembles Nirn except colder, darker and more beaten and violent; according to some a premonition of the future of Nirn itself.
I imagined it, instead of ONLY slave pens and such, to have many other features as well, but overall being very dangerous and foggy. I think the excellent weather animations in Skyrim could really capture the brutality of the land itself. I would like to see very dangerous waters, lakes or a sea, with many horrible monsters lurking in the depths. I think it would be very immersive and, well, fun to be scampering across this dark and grey land, fearing capture and imprisonment, where everywhere you look you find diseased slaves and broken lives. Maybe you can set them free, or maybe you have other business there. Be careful of the demons.
Some might say that "they just did Fallout!", but I see this very differently. There is a world they could do to make this a unique land. And besides, I would like Moonshadow or The Hunting Grounds to appear on the next gen of consoles, so graphics can do the art real justice.
Also, if anyone has any pictures from the webz that allude to this, please post.