Originally home to the all but extinct humans, this world felt the tragedy of the Sundering the worst. All life on Kieros was destroyed during the Sundering, but the magical backlash left the spirits of the dead stranded amongst their corpses. As a result, a wide variety of undead come from shards of Kieros, and many of its ancient stately cities have become necropoli.
Kieros is entirely dead, down to the bacteria that usually allow plants to grow in soil. However, many beings other than the sentient biped that once ruled the world, were effected by the magic that made so many undead here. Undead plants and animals form ghostly or otherwise undead ecosystems that exist in the spaces between the great Golgothas that once were cities.