Descent into Undermountain
“Undermountain? Ah, yes. It’s a areat place to have fun, and it’s the most famous battlefield upon which a wet-eared wanderer can earn a reputation as a veteran adventurer. Of course, Undermountain is also the largest known mass grave in Faerûn today.”
- Elminster of Shadowdale
This ancient dungeon started as a mine and dwelling of dwarves belonging to the Melairkyn Clan. In the centuries since the dwarves were driven out it has been the home of drow, duergar, powerful wizards, criminal groups, and convicted felons.
The most famous of those to control the halls of Undermountain was Halaster Blackcloak, the Mad Mage. He and his apprentices explored the ruins and laid claim to many areas. Over the next thousand years they populated these areas with various monsters, magical experiments, numerous portals and traps. Around 1306 DR the City of Waterdeep started exiling convicted felons to the depths of Undermountain.