Pandemonium is the realm that lies between the high heavens & the burning hell,it's where the angels & demons fought the eternal conflict. It's the place where Archangel Malthael first found the eye of Anu & recognized its importance followed by him renaming it the world stone & declaring that the angels should protect it & where the angels first encountered the demons who sought to control the world stone & its powers & so the Archangel Tyrael saw the construction of the Pandemonium Fortress to protect it
Pandemonium is the place where the second half of Act V takes place
Areas within Realm of Pandemonium
- The Pandemonium Gate(technically it's in the high heavens)
- Path of War/Abandoned Siege Camp
- Battlefields of Eternity
- Siege Outpost
- The Ram
- Pandemonium Fortress Level 1
- Pandemonium Fortress Level 2
- Pandemonium Fortress Level 3
- Malthael Boss Arena (this is how it is listed in achievements but may change in final version of game)