Ellaniath

Ellaniath was the name of Vhaeraun's realm,   the drow deity of thievery. It served as his base of operation and as the place of his followers' afterlife.

Location
Ellaniath was a realm, with - uncharacteristically for a location - a moving history in the physical sense.

It was originally situated in Colothys, the fourth layer of Carceri under the Great Wheel Cosmology. At some point in the 14 DR, the planes shifted into the World Tree cosmology and Ellaniath was moved into the Demonweb Pits and hang among the strands as one of the baubles. After the Silence of Lolth, Lolth yanked the Demonweb Pits out and turned them into an independent realm, Ellaniath returned to Colothys. After Vhaeraun was killed by Eilistraee, Ellaniath merged with his sister’s portion of Arvandor and remained there after she died. Over the course of the Second Sundering, both Vhaeraun and Eilistraee returned, though it was not clear what happened to their realms.

Features
Nobody outside of Ellaniath, save the ruling god, had an idea, where the realm was located, apart from the very general knowledge "somewhere on Colothys", and how it looked like. Vhaeraun wiped the memories of those who stumbled on his realm, which was considered a demonstration of his abilities as a thief.

During its time in the Demonweb Pits, it hang at one of the strands of the webs there as a bauble like the other drow deities’ realms.

During the realm’s time on Arvandor, Ellaniath merged with Eilistraee's realm, the drow goddess of moonlight. the it looked like a forest under perpetual night with the half moon being the only source of light. The forest had shining moonstones as decoration, half among them gradually lost their light after Ellaniath's incorporation until they became pitch black.

Function
Ellaniath was Vhaeraun’s realm. It served as his base of operation.

During the realm’s time on the Demonweb Pits, Vhaeraun spent his time operating outside of his realm in Lolth’s territory. These operations reached from time to time levels, that made it impossible for his mother to endure them. Every time she spent effort against him, he fled into Ellaniath, which served as his hiding place, which proved over and over again as safe.

It was known that the drow deities maintained portals to the Abyss in their realms.

Power over the Realm
Vhaeraun, as a lesser deity, could not only alter his realm in some fashion like setting temperatures as he liked or fill it with special sensory information, like light, sound and smell, when it came down to sound, he could also make intelligible speech as background sounds in his realm.

Vhaeraun, as a lesser deity, could also control his realm's link to the Astral Plane, effectively controlling how good magical travel worked within his realm.

Effects
As part of the Demonweb Pits, Ellaniath was divinely morphic, meaning Vhaeraun had an easy causing physical changes in his realm. While there, Ellaniath was mildly chaotic and strongly evil aligned, meaning that the plane itself worked against individuals who followed lawful philosophies by weakening their power of personality, and limiting in general the mental capacities of those who weren't evil. The realm had also a strong faith factor, meaning that those, who didn't follow the Dark Seldarine suffered even more limitations, with followers of the Seldarine suffering a drop in mental capacity more severe than others.

Once the realm was in Carceri, Ellaniath was mildly evil aligned and still divinely morphic.

Inhabitants
The realm was inhabited by his petitioners, his dead followers' souls, Among the petitioners, the vhaeraths were special in that they retained memories and skills in life and could also leave Ellaniath and weren’t bound to their plane like others.

Like other deities, Vhaeraun changed petitioners of followers who distinguished themselves in service to him into his servitors as a reward, these included demodands (farastu, kelubar, shator); mephits (air, earth, smoke), shadows, shadow dragons, shadow fiends and yeth hounds.