The chamber of Khaz'mul

The Chamber of Khaz'mul is rumored to be an undiscovered secret piece of Uldaman, it is actually a chamber directly off of the Map Chamber. It is impossible to enter it without the  [Staff of Prehistoria], broken into two pieces that are the  [Gni'kiv Medallion] and  [The Shaft of Tsol].[1][2]

To enter the room, it is necessary to place the reconstituted staff in a certain point of the Map Chamber in order to activate a magic door. It is said that the chamber holds the secrets of Uldaman, but to gain entrance, one must first defeat the titanic watcher; Ironaya, who guards inside the chamber itself.[3][2]