Though first recorded fairly early by the Guvners, the Steaming Fen — the 14th layer of the Abyss — is far off the beaten trail, avoided even by the tanar'ri (out of superstition largely more than anything). This is because it was here that the tanar'ri were once kept low, here that once held power over the whole of the Abyss. It is the Steaming Fen where the Queen of Chaos holds court, and though she's well-weakened since the days of the War Between Law and Chaos, she still survives even today with hundreds of her spawn, the spyder-fiends. Since her defeat and the following Upheaval that nearly wiped out the obyriths, she's held almost no influence upon the planes, her attention fully on the recovery of the Rod of Seven Parts and the restoration of her beloved consort, Miska the Wolf-Spider. Still, it's rare the person willing enough to risk her ire by entering upon her realm, today a nearly-empty land with little to nothing that would even draw a person to it compared to the risk they would take.
The vast majority of the Steaming Fen is nothing but a boiling, briny ocean never more than half a mile deep, completely still and barren of life but for spyder-fiends or, even more rarely, various spawn of Dagon that can survive the heat. While this sea has no direct connection with the Abyssian Ocean or the River Styx, it does still connect to the Shadowsea along specific winding pathways. Beneath the waters, ancient ruins dating back to before the Upheaval can be found on rare occasion, leading some to theorize that the current nature of the realm was brought about during the rebellion, as a strike against the obyriths. While the occasional mountain does break the surface here and there, the only significant bit of land is Djimadorad, a great 20-mile peak stretching into a violet, sunless sky. Even by the eruption of the War, this mountain had already served for centuries as the castle of the Queen, hundreds of miles of tunnel dug through its mass by tanar'ri servitors; this same castle still stands today, far too massive an edifice for even the full force of the tanar'ri to do any lasting harm to. Here, the Queen of Chaos and her spyder-fiends reside, for the most part heedless of whatever might transpire in her realm so long as it doesn't interfere with her goals.
- The Rod of Seven Parts - Book III: Might and Menace, pp.19-21