"Welcome! Welcome brave patrons of the Yawning Portal! Tonight we have quite a treat for you! We have not one, not two, but three courageous bands of adventurers prepared to brave the horrors of Halaster’s dark dungeon! For those of my customers who are unaware, Halaster Blackcloak was a sorcerer gone mad in ages long ago. There are rumors he came from Netheril, or from the far east. Still others claim he hailed from the Cradlelands, the lost kingdoms that gave rise to Faerûn and the distant lands of Kara-Tur! Whatever his origins, the stories all agree on one thing: that over a thousand years ago, he left all dealings of men, and came to Mount Waterdeep accompanied by seven of his apprentices. For years they worked the inner depths of the mountain, carving out vast halls and summoning the most nefarious of beasts this world has ever seen! They say that Halaster’s dealings with his summoned servitors changed him, that the lack of human contact and the company he kept in such a maddeningly labyrinthine mountain drove him to insanity. I say he was always a madman, and that he took the depths for his own, to act out his sick fantasies and laugh at the ill-fortunes of the men who ventured into his realm. He created the world’s most wicked traps, designed to amuse him as he watched the suffering of any who dared trespass. As the years passed, his apprentices lost contact with him, and over the years as they sought to find him, they found only death and traps and beasts wandering the halls, but no sign of the wizard. He was gone! There are rumors that there are even more layers to this pit than ever known, and that he hides within their depths, watching the deaths of brave adventurers. If so, no one has seen them and returned. Now, a thousand years since first he stepped into Undermountain, his dungeon riddled with hundreds of deathtraps, the word is out that Halaster is dead! Is he, says I? Some say he discovered a method to regain his youth eternally, and that he still roams the mountain, watching, and waiting for poor fools to gut themselves on his vile dungeon. Either way, the treasures that lie deep below are untold, and I myself have made away with barely my life intact, and my arms full of treasures beyond my wildest dreams. Tonight, three troupes of adventurers go into the darkness. Will they meet an untimely doom? Or escape with the most powerful artifacts that Undermountain has to offer?"Undermountain! The biggest, bestest, most stupendous of all megadungeons! King of character killing! Lord of lavish luster! If you want your players to live the rest of their meager lives in a dungeon, this is the place to take them. If they delve deep enough, they may even gain the chance to die in the deepest layers of the mad wizard's lair itself! But I am getting ahead of myself, we need to start at the beginning of this epic death trap. I speak of course, of the Yawning Portal.
The Yawning Portal is only one of a several entrances into Undermountain, but it is the primary one and generally acknowledged to be the "beginning" of the dungeon. It is an inn built around a massive pit in the earth with a winch that lowers players one at a time down into the megadungeon. The owner of the inn, a man who made his fortune by delving into the dangers below, charges a modest fee for those wanting to enter the pit. His primary profits however come from the betting of the tavern's patrons on which groups will return alive and which won't. Delving parties are allowed to bet on themselves, and most bet a hefty sum, on account of not needing the money if they're dead.
It should be noted that Undermountain is created by an insane wizard named Halaster Blackcloak. It's structure and design is not subject to typical architectural conditions. Flagstones change color and stone; tight tiny rooms open up into massive coliseums; hallways end in dead ends for no apparent reason; and worst of all there are no bathrooms. The dungeon does not make sense, and to think too much upon it would be pointless. As for its creator Halaster, the wizard was known for having a particularly lethal sense of humor, and would take pleasure in harassing people who went into his dungeon. Not always so directly, he preferred to lead them to their deaths in rather elaborate ways with random teleportations and traps. He seemed to be particularly fond of the "out of the oven and into the fire" style of dungeon crafting. And speaking of teleportation, the wizard's magical seals on the entirety of the dungeon are so powerful that it is impossible to teleport or scry anywhere into it. Mechanically, this kept high level parties in check, as they were unable to use their powerful magic to make a mockery of the dungeon's dangers.
Canonically, Undermountain is beneath the city of Waterdeep on the Forgotten Realms campaign's Sword Coast. However the megadungeon was designed with the ability to apply it to any fantasy setting rather easily. For myself, I once had a catastrophic event occur to the city of Waterdeep. So devastating that years after the players had explored a portion of the epic dungeon, it was destroyed into a massive hole. The players descended into it to find what I called the Undergrave, an enormous grave made of the bodies of the local Waterdhavians. They sloshed through the piles of bodies; along the way fighting all types of horrific undead, turned unholy by the Undergrave's dark magic. They found remnants of the city above them, and went through areas of the former dungeon. From this they descended to a lower level of enormous dug out caverns, created by a linnorm I had built a mythology around. A beast so big and so ancient the dwarves had worshipped it as a god back when they were simply proto-dwarves, mere shadows of what they would one day become. In the darkness and the fear, they encountered this horrific nightmare, and knew only the terror of its endless maw. The adventure continued on but the point is made: Undermountain can be whatever you make of it. But it is important to me, whenever I introduce it into a campaign, that it be the scariest, biggest, most intense dungeon the world has to offer. That, to me, is Undermountain's spirit and intention.
I apologize for the lateness in the day recently in posting, I've been rather busy these past few days and fell behind. Tomorrow though I plan to be back on track to finish this challenge. Thanks for reading, stay tuned tomorrow for "V is for Vancian Magic".
Forgotten Realms Wiki Undermountain
Wizards of the Coast Return to Undermountain