I heard a rumor that there is a published reference to a layer of the Abyss that is controlled/populated by celestials. Is this true? If so, what source mentions this?
I'm really just curious about such an oddity on the planes.
It's from a 2e Planescape supplement called Faces of Evil: The Fiends, and while it doesn't appear to be a whole layer, it is all data I can find on official stuff existing on that layer.
In short, on the 403rd layer of the Abyss, a Fallen Archon rules the City of Confusion, and several other Fallen Archons are her minions. They try to cure the mortals that come across the city, purify their souls, so they can go to Celestia. They fail at it, however, because these Fallen Archons have become as Chaotic Evil as the plane they live on. They are just in denial about this.
After hints from @Lord_Gareth and a fair bit of searching, I found what I was looking for: Androlynne, Abyssal Layer 471. It is detailed on page 148 of the D&D 3.5 Fiendish Codex I - Hordes of the Abyss.
It is ruled by an Obyrith, Pale Night, so it isn't really controlled by Celestials. Eladrin children are bound here, and Good creatures wage a never-ending war on this Layer in order to rescue and/or defend them. The Good creatures have maintained such a presence on this layer that it has been transformed from a nightmare landscape to a bright rainbow-hued battleground.