The underdark no longer exists. Massive earthquakes have caused the entirety of it to collapse in on itself, killing all inhabitants that couldn't escape within the first few seconds of the quakes. This page has been retained for historical purposes.
The Underdark is not a plane, but instead a massive series of caves and tunnels beneath much of Hope and the oceans around it. The underdark stretches for miles and miles at a time without outlets to the surface, and is filled with jagged rocks, sudden sheer drops and water-filled passageways... some of which lead to the Abyss itself.
The Underdark is a dangerous place to travel. Though some Dwarves have found entrances to its deeper tunnels and emerged with their lives, many others have had entire bands consumed or enslaved by the creatures that dwell below the earth. Most have become food for the Illithids or slaves of the Tsochar. A similar fate awaits all who delve too deep.
The only race to call the underdark and it alone their home are the Dark Faeli, who live in tight knit bands that move often, unhindered by the Dark Lady's children. While once solely the servants of the Asharra, her disappearance has caused many to doubt. With the recent invasion of the dragon god Namtar and his Deep Dragons, many have converted to worshiping him and his father Minrhet. Other Dark Faeli have encountered the Genasi and have turned to the atheistic belief of Marcosim. Those true to Asharra torture these atheists in reverence to their dark goddess, while those who have turned to Namtar grant them the mercy of a swift death.
The original inhabitants of the underdark were Asharra's servants. The Illithids live in small groups scattered throughout the tunnels, usually not far from parts of the surface that are home to towns or cities. Aboleths lurk in the deepest, water-filled tunnels to ponder and plan. The Tsochar breed madly in the dark before emerging on the surface to seek new hosts.