Hey, I searched around and found that few ppl had posted something likely but not inside this cave/instance w/e, I first read the post from Kezah how to get under northrend and thought hey why not check it out cause im rly bored. So when I did go into icecrown citadel instead of going down under I just flew right down into the green light and happend to land in an instance looks abit like ehm anub' rehkan or smt. well heres some photoes from it, sorry if its a repost. I found it to look quite cool.
The Faceless Lurkers(mobs inside) says: Shur'nab... shur'nab... Yogg-Saron!