War of the Burning Sands
The Gray is an echo of Athas, an otherworld of shadows and ghosts. In this realm, the restless spirits of the dead linger amid the haunted ruins of great cities. Some sources call this otherworld “the Shadowfell” or “the Plane of Shadow.” Like the Lands Within the Wind, the Gray is home to strange and powerful creatures, including mighty shadow giants, fearsome nightmare beasts, and a race of devils that were trapped in the Gray when the connection between their home plane and Athas withered. Unlike the Eladrin of the fey realm, the denizens of the Gray are much more hostile to mortals who venture into their domain.
Many erudite thinkers believe that the Gray acts as a barrier between Athas and other realms beyond, and that long ago, the domains of the gods could be found in starry seas beyond the Gray. But the Astral Sea has been empty for ages. No godly domains remain within reach of mortal travelers, and the easy connections between the outer planes and Athas have been severed. For all that is known, Athas is isolated and alone, and some wonder whether this might have been done intentionally by some powerful being long ago.