Oscon's Fortress Level III - Spoilers
If you were paying attention at the end of the last level, then you know that the "Word is still...". Answer STILL to the magic mouth at 12n/2e to activate the magic stairs at 14n/1e. Of course, I don't really see the point. You can use the portals in the northern area near the teleporter loop. Perhaps they meant to make those impossible to get to? 
