I just wanted to point out that "the upside-down sinners," is a reference to and a recreation of a locale in John Carpenter's, "Big Trouble in Little China."
http://www.imdb.com/title/tt0090728/
If you haven't already seen this movie you should immediately. It also inspired the Mortal Kombat series and is referenced in the in-game item, "the six demon bag" (wind, fire...that sort of thing).
In the movie they reference several "Chinese Hells."
# The Hell of Being Cut to Pieces
# The Hell of Boiling Oil
# The Hell of the Upside Down Sinners
# The Hell Where People are Skinned Alive
# The Hell of the Oily Dragon
The only one that actually shows up is the Hell of the Upside-down Sinners. It is just as shown in lower Karazhan and quite scary.
If there are any other oldtimers reading this post they'll back me up.