Source: The First World, Realm of the Fey, pg(s). 19
Nighthold is a realm on the First World. Once ruled by the Eldest Count Ranalc and embodying the chaos of creation and destruction, it fell apart after he was exiled, its buildings crumbling into ruins and its inhabitants turning against each other.
Nighthold is a dark, chaotic, terrifying realm, filled with howling winds and stone ruins of buildings, lit only by flames springing up from the ground. Although Count Ranalc is no longer present, the spectre of his presence still looms, and the ever-churning lands continue to reflect his personality and emotions. Nighthold is plagued by roving shadowstorms that cover huge areas in darkness.
The border of Nighthold is marked by the Lightline, a series of lanterns that serve as a focus for enchantments that prevent it from expanding, established when it became clear that the First World would not absorb Nighthold back even when Count Ranalc is absent.
One of the few areas untouched by Nighthold's constant chaos is the Traitor's Chair, which once served as Count Ranalc's seat of power. It is said that a creature who successfully sits on the chair will become an Eldest and the new ruler of Nighthold, but all who have attempted to do so have been devoured by their own shadows.
Nighthold no longer embodies the duality of creation and destruction; the creatures it births are now all deformed or stillborn mockeries of its glorious past. Many non-good fey are drawn to it, while good creatures risk becoming twisted and shadowy if they spend too much time in Nighthold. Numerous creatures have also come to Nighthold from the Shadow Plane via the portals that frequently rip themselves open between the planes. Some of Count Ranalc's new servants have taken the ruins of Nighthold to stage shadowy campaigns in his name.
A small number of ankous, who remained loyal to Count Ranalc after his disappearance—unlike the rest of their race—have stayed in Nighthold in an enormous well called Kyrvost to watch over it until their master returns.