The most deadly dungeon ever devised! High-level characters brave the unexplored corridors of Deepearth to confront perhaps the most feared adversary in the AD&D game. The second chapter of the Bloodstone Pass saga follows the conclusion of the desperate war against the bandit army. A cold and bitter winter drives the villagers to the edge of starvation, and numerous horrors strike the town of Bloodstone Pass. Join the adventure as the heroes explore the depths of the ancient bloostone mines, now inhabited by fearsome demons. There they hope to uncover the fantastic treasures rumored to exist in the unknown darkness. But deep within the mines, all is not what it seems.... This module uses the new rules from the Dungeoneer's Survival Guide and Wilderness Survival Guide. The adventure also includes optional BATTLESYSTEM scenarios fought entirely underground. These supplementary products are not required to play the adventure, however. TSR 9168

A special underworld encounter from DUNGEON Adventures! The toll may be higher than you can afford... To travel further into the Underdark the party must cross a bridge spanning a deep chasm. But to cross, they must pay the toll, or risk another route. Pgs. 47-54

With allies gained from denizens of the Underdark, the former drown enclave of Szith Morcane is on the precipice of being retaken. During the battle for Szith Morcane, secrets of the drow community are revealed. What will you do with this knowledge, and how will it affect the outcome of the conflict?

"The Aboleth's Grotto" is a nihileth lair suitable for four 10th-level characters. The adventure can be completed in one session. The small town of Springwell harbors a secret that almost nobody knows about, and those who do conveniently ignore: it sights right over an unoccupied settlement of the deep caverns of the underworld.

The kuo-toa are a piscine race with a psychic affliction that makes them behave erratically and invent gods when feeling threatened. That same affliction gives them the power to bring those gods to life. Blibdoolpoolp is the most widely worshipped, and thus most powerful, of their gods. Blibdoolpoolp views the kuo-toa as her children despite having been born after them. Like all good mothers, she nurtures and protects. One of her chief concerns is understanding the kuo-toa’s psychic affliction, which causes them to undermine themselves whenever they strive for greatness. She discovers that a corrupted elder brain deep in the Underdark has a connection to the race; though the connection gives them psychic powers, it also turns them into powerless thralls, explaining their self destructive behaviors. Constrained by the same leash on her children, Blibdoolpoolp seeks adventurers to destroy the elder brain. Its death would free the kuo-toa, but potentially at great cost: if the kuo-toa lose their powers, will Blibdoolpoolp die?

The Shattered Circle is an AD&D® adventure for four to six player characters of 1st to 3rd level. For many ages, the standing stones known as the Circle of Cahervaniel have stood on a grassy hilltop, unremarkable and unmenacing, but something has changed. A powerful artifact deep within the earth has been uncovered, and its evil power has corrupted the recent inhabitants of a dungeon complex. The chitine live within, a cross between humans and spiders created by the drow, but trying to live a quiet existence. The evil Foundingstone has corrupted some of the chitine, and split their society in two, bringing them to conflict. Adventurers who navigate the chitine factions and dangerous dungeon will need to end the threat of the Foundingstone and the solve the mystery of the strange dark unicorn Mizar that has appeared recently around the stones. Interestingly, one of the unique magic items in this adventure, Icerazor - is said to have grown from a shard of Frostrazor, a sword that appears in a famous later adventure - Return to White Plume Mountain. There is a brief mention of Suloise, so it can be considered a Greyhawk adventure, but clearly states it can be placed anywhere.

A dwarven expedition has stopped in Mulmaster for much-needed supplies. Furgis Boltsmelter, their founder and leader, is looking for some “no questions asked” protection for the duration of his stay in the city. Whatever he is trying to protect may not stay hidden for long. Can you keep his secret treasure out of the wrong hands? A four-hour adventure for 1st-4th level characters.

On a nameless, featureless demi-plane the Tarrasque rages across an all-encompassing nothingness. Last seen on Faerun a century ago during the cataclysm of Odobaz, the battle mage order of the Eldritch Storm sacrificed itself to banish the mighty titan to its demi-plane prison. Now a foul power emerges in the High Ice and nightmare visions of the Tarrasque trampling cities wrack the minds of the living—can your adventurers defeat the Horror Under the Mountain?

The Adventurers arrive at a drow outpost in the Underdark. They must either dispose of the drow or ally with them against the invading legions of Orcus!

This material was originally published as two separate adventures, D1: "Descent into the Depths of the Earth" and D2: "Shrine of the Kuo-Toa." Contained herein are referee notes, background information, maps, and exploration keys intended for use with the Advanced Dungeons & Dragons rules. The adventure can be used alone or as part of an extended adventure that begins with G1-3: "Against the Giants" and continues with D3: "The Vault of the Drow" and Q1: "Queen of the Demonweb Pits." TSR 9059

The greatness of a dwarven citadel is measured by its greatness of wealth. The dwarves steadily work mines and forges to fuel the wealth needed to make their presence known throughout the realms. Unfortunately, this also makes them known to those that would seek the opportunity to steal their glory and riches. This story occurs in a place that has experienced this struggle for millennia. New threats emerge as old threats become rivals through the tides of time. This story... your story... is another chapter of this ancient struggle.

A band of evil fey, led by a corrupt bralani, has raided an eladrin city and kidnapped several respected elders. The fomorian king claims the rogues don’t act on his behalf, but the eladrin city threatens the fomorians all the same. To prevent war, the PCs travel through the Underdark of the Feywild—a wondrous place filled with the beautiful and the horrifying—in search of the evil fey and their captives. Pgs. 96-101

Originally designed as a convention module, this adventure sends the heroes into the underdark to do battle against the mysterious denizens of the deep! A drow housemistress commissions the characters to acquire a mysterious weapon known to be in the hands of her dark elf enemies. Locating, identifying, and acquiring the magical weapon leads the heroes on a great trek across the underdeep, where they must battle svirfneblin, a powerful lich, and enemy drow. This adventure us specifically designed for play by drow characters, but can be used with any adventuring party. Pregenerated drow characters are included.

Ruins of the Grendleroot is a book of ten easy-to-prep and easy-to-run adventures for the fifth edition of the world's most popular fantasy roleplaying game. Designed for characters of 1st to 5th level, these adventures take place in the caverns, chambers, tunnels, and ruins of Blackclaw Mountain, within which lurks a strange otherworldly sentience known as the Grendleroot. Ruins of the Grendleroot focuses on the sense of mystery and wonder that comes from exploring ancient ruins and lost chambers. The central hub of these adventures, Deepdelver's Enclave, is a frontier outpost overlooking the ruined city of Shadowreach, set deep within the mountain. In Deepdelver's Enclave, adventurers and explorers recount tales of their explorations, trade treasure and artifacts, and enjoy their shared love of uncovering the mysteries of the mountain.

The Fate of Faerûn Lies in Shadowy Darkness! Daggerdale is reeling from a sudden series of murderous drow raids. As a grave threat to the entire surface world develops in the war-torn dark elf city of Maerimydra, intrepid heroes must discover its source and destroy it, if they can.

The Underdark is a subterranean wonderland, a vast and twisted labyrinth where fear reigns. It is the home of horrific monsters that have never seen the light of day. It is here that the dark elf Gromph Baenre, Archmage of Menzoberranzan, casts a foul spell meant to ignite a magical energy that suffuses the Underdark and tears open portals to the demonic Abyss. What steps through surprises even him, and from that moment on, the insanity that pervades the Underdark escalates and threatens to shake the Forgotten Realms to its foundations. Stop the madness before it consumes you! Note for DMs: This adventure is not for the faint of hearted, to run or to play. The module starts with 10 NPCs traveling with the party through the grueling Underdark. This number can grow. The encounters within the book are often incredibly deadly for the characters that would be going through it. This is because the module expects them to run or talk their way through the events, or, in some cases, the module expects them to lose. If your players aren't the kind of party to run, talk, or surrender, do not get this adventure. The module almost requires that you use milestone leveling because the experience provided does not commonly get players to the levels they should be once they get to certain milestones in the story (7th when they leave the underdark, 15th when they face the demon lords.) Good luck and happy questing.

Agents of the fire giants of Maerimydra, a city in the Underdark, have overtaken the drow outpost of Szith Morcane. The factions seek out adventurers to free the outpost’s leaders for questioning on the giants’ activities. Can you extricate them before it’s too late?

The time has come for the brave and the bold to put an end to the machinations of Maerimydra’s demonic occupiers and their fiendish fire giant ruler. This will be no mean feat; the city is a cesspit of corruption and madness. You will have help, however, as an unlikely group of allies have gathered to your side in the Underdark beneath Faerûn. Danger, glory, and redemption await those brave enough to seize it. With allies gained from denizens of the Underdark, the former drown enclave of Szith Morcane is on the precipice of being retaken. During the battle for Szith Morcane, secrets of the drow community are revealed. What will you do with this knowledge, and how will it affect the outcome of the conflict?

While in the peculiar village of Basht, a town full of strange customs and superstitions, an elderly woman asks you to check in on her grandson, a Gondite tinkerer testing out his latest invention in a nearby cavern. Sounds easy enough, right? A Two-Four Hour Adventure for 5th-10th Level Characters This adventure originally debuted as custom content for the 2019 U-Con convention in Ann Arbor, Michigan. Visit them at https://www.ucon-gaming.org/

Of all the inhospitable domains in the RAVENLOFT@ campaign world, Bluetspur is the cruelest and most gruesome. Nothing grows in the endless night, and lightning periodically falls like rain. The only place to escape those storms is inside the mind flayers' complex under Mt. Makab, but that is the last place where any sane person would want to go. The High Master Illithid has been hatching black plots by hatching vampiric mind flayers in his laboratories! His prodigies are horribly insane, but if he can complete his plans, he will achieve a new level of dark immortality. A pair of heroes has stolen the key to his success, but they have paid a heavy price for their bravery and are in desperate need of aid unlooked for. Meanwhile, the Lord of the Realm watches over the proceedings and plays havoc with the wits of both sides, sapping strength and will with all-powerful thoughts of darkness. A party of adventurers will need all of their skills to escape this black domain without the loss of life, power, or sanity! Enter now the perpetual twilight realm of Bluetspur, home to mind flayers, a land of relentless nightmares. There's no rest for the wicked or the good in this domain. Once caught within the borders of this desolate land, the characters must complete their mission without delay or lose their minds and become slaves of the Lord of Bluetspur. TSR 9264, from 1992