Get under Zuldrak (possibly other places)

[afarina1]

I was running thru Draktharon keep on my rogue and I got to the First boss Trollgore. I stealthed up behind him and hit killing spree (I am also using the glyph of killing spree) which of course killed him almost instantly. When he died and killing spree sent me back to my original spot it ported me underneath the instance and I was free to roam in a mobless version of zuldrak. The only way I was able to get out was by commiting suicide with my sacrificial dagger. I also had this happen in SOO where i got ported under the instance and there was a big checkered cube under the world when fighting the shamans. This seems to happen when on hills when killing spree goes to send you back to the spot that you were at when you used it.