This adventure is written with the intent that it takes place in the subterranean world called the Underdark in the world of Forgotten Realms, although it may be placed in other settings. Within the Underdark, Cyrog's lair can be placed anywhere though it is stated to be thousands of miles east of Gravenhollow. If you are running Out of the Abyss, you may want to have your players see the vision Cyrog Lives! Hail Orcus! (OOTA, 158). Additionally, it is recommended that this adventure be used for a party of 4 to 6 players, level 9 to 12. While merely hinted at through visions in Out of the Abyss, Orcus is roaming the Underdark unchallenged with an army of mind flayers at his disposal. Cyrog, the elder brain of a mind flayer colony in the Underdark has died. The demon lord Orcus has reanimated and taken control of it. The hive of mind flayers is now bent to Orcus's will through Cyrog as he strives to make all life in the multiverse into a vast undead horde under his control. The adventurers are contacted by a patron who gives them a special item (such as brain worms) to suppress their brain waves and make it possible to infiltrate the Cyrog's Lair without immediate detection. The adventurers must defeat or otherwise subdue mind flayers and a few guards, override the elder brain's mechanical defense system, and slay Cyrog.

In the search for allies in the Underdark, you are called upon to travel through the recently opened Waydown sinkhole to find the lost myconid colony of Sporedome. It is said that they once cultivated a strain of mushrooms that could protect one from falling into madness. Can this be the cure for the rapidly spreading onslaught of insanity?

Sarkt is an illithid sorcerer. It was cast out of its community for its heretical studies (Sarkt was in fact, lucky to escape alive). It didn't take the cunning creature long to pick up a few thralls and find a new place to live, safe from the murderous intentions of its companions. Sarkt dwells in the subterranean ruins of an ancient shrine to Blibdoolpoolp, the crustacean-headed deity of the kuo-toas. This shrine lies on the fringe of a region controlled by kuo-toas, but since Sarkt's arrival, the fishmen avoid the area. A few unfortunate kuo-toas now serve Sarkt as thralls and maintain the illusion that the shrine serves Blibdoolpoolp. Pgs. 82-88

An escaped duergar slave stumbles into the village of Elventree. With her she brings a malady that grips the small settlement in a bout of madness that seems unshakable. Can you find the source of the madness and save yourself and the village’s inhabitants? A four-hour adventure for 5th-10th level characters.

In this adventure, the Lord Commander of the Sharn Watch hires the heroes to investigate the murder of an actress. The investigation quickly spirals into a bloody dispute involving a dead wizard’s spell-book, political rivalries, and secrets that might foment war among the Five Nations. Pgs. 1-37

A powerful new narcotic is making its way through the Spine of the World. Behind it is a secret that could change everything! Explore a lost city and discover the secrets hidden by the gods themselves. (TW: some drug use and the possibility for players to use drugs)

A mind flayer has called for a massive conference of monsters in the Underdark beneath Hillsfar. Trolls, umber hulks, demons, and more have answered the illithid's call. To infiltrate this gruesome menagerie, you must embrace the monster within yourself.

Having put down a rising of giants, it was discovered that the motivating force behind their depredations was that of long-forgotten evil - the Dark Elves. Determined to seek out these creatures, a body of doughty adventurers mounted an expedition to learn the strength of the Drow and bring retribution to them (DUNGEON MODULE D1, DESCENT INTO THE DEPTHS OF THE EARTH). This module contains background information, a large-scale referee's map with a matching partial map for players, referee's notes, special exploration and encounter pieces, a large map detailing a temple complex area, encounter and map matrix keys, and an additional section pertaining to a pair of unique new creatures for use with this module and the game as a whole. A complete setting for play of ADVANCED DUNGEONS & DRAGONS is contained herein. This module can be played alone, as the second part of a series of three modules (with DESCENT INTO THE DEPTHS OF THE EARTH, D1, and VAULT OF THE DROW, D3), or as the fourth part of a continuing scenario (DUNGEON MODULES G1, G2, G3, D1, D2, D3, and Q1, QUEEN OF THE DEMONWEB PITS). TSR 9020, From 1978

TENTACLES. WHY DID IT HAVE TO BE TENTACLES? A colony of deep gnomes have had their main water source taken over by a group of kuo-toa, but are the fishy folk really the ones to blame for leaving the gem-loving svirfneblin thirsty?… This adventure was originally made for a West Marches campaign, but is designed to easily fit into any standard fantasy setting. There are many areas to insert plot hooks for your own world or campaign. A 4-hour adventure for 5th-7th level characters by ALAN TUCKER

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 Baronies of Erlkazar, once a prosperous region of pastoral tranquility, is now a land of nightmares and dread. Bandit armies plague the region, terrorizing the populace and surrounding countries of Calimshan, Tethyr, Amn, and Turmish. Though these threats are terrifying enough, it is nothing compared to what awaits the people of Erlkazar at night. In caves, tombs, and subterranean communities beneath the seemingly pastoral villages of Erlkazar live the secretive Night Barony. Ruled by the vampire Saestra and her legions of darkness, these monstrous denizens of the Five Baronies are the real power in the region. The country’s only hope of liberation is you.

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!

Tonight, a ceremony of light is taking place on the surface. Meanwhile, a world away in the city of spiders, a drow matron solidifies a pact with soul-consuming entities who require great sacrifices in trade for unimaginable power. Drow eyes turn to the surface. This book contains a mega-adventure and setting, taking characters across the surface and into the depths of the world. Adventurers will meet unique denizens, battle horrors of the Underworld, explore epic locations, and fight to stop the rise of the drow.

Hellmaw Island is a place of legend, a hidden fortress protecting the greatest treasures in the world. Rumour says it is guarded by wicked traps, bizarre and terrifying monsters, and maddening enchantments. Our heroes have been tasked with penetrating this mysterious stronghold, and they will find it to be stranger and more dangerous than anything they have encountered before. Assault on Hellmaw Island is a 5th Edition Dungeons & Dragons adventure for characters of levels 5-10. It will take 4-8 hours to complete.

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/

This 4 hour adventure for 3rd level characters begins in a prison cell where the adventurers must figure out a way to escape, acquire weapons and armor to defend themselves more effectively, and most importantly, escape a repurposed dwarven forge that has been appropriated by a fire giant who uses slave labor and even a captured red dragon wyrmling to smelt ore and forge an arsenal under the volcano Mt. Hotenow.

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

As a member of a bold party of adventurers, you and your associates have trekked far into what seems to be a whole underworld of subterranean tunnels -- arteries connecting endless caves and caverns which honeycomb the foundations of the lands beneath the sun. Your expedition has dogged the heels of the Dark Elves who caused great woe and then fled underground. This module can be played alone, as the conclusion to module D1 & D2: "Descent into the Depths of the Earth," or as the third module in a series that forms a special extended adventure (G1-G3: "Against the Giants"; D1-D2: "Descent into the Depths"; and Q1: "Queen of the Demonweb Pits"). TSR 9021

In Prisoners of the Drow, a band of adventurers storm a drow outpost, confront the drow mage in charge of it, and rescue prisoners held within. The heroes must bypass traps and devious defenses to reach their goal and accomplish their mission. The adventure is designed for a party of five adventurers between levels nine and twelve. It features: Encounters by Level - Varying types and quantities of creatures are suggested based on the party's actual level, allowing each encounter to present the appropriate challenge to the party. Encounter Notes - Suggestions for how to run combats are provided for game masters who place an emphasis on engaging, tactical battles. Inciting Action - Suggestions for ways to present the adventure to players are provided. Ease of Use - The format and style of the document allows the game master to find information quickly while running the game at the table. Detailed Maps - What's an adventure without maps? Not much else to say here. This adventure is designed as the first in a two-part series. The second adventure Into the City of Spiders takes the adventurers into a drow compound far from the surface. https://www.drivethrurpg.com/product/247674/Into-the-City-of-Spiders

How’d you get here? Let me explain... No, there is too much. Let me sum up. Rescued a retired hero's hapless nephew from goblins at some ruins on a hill Found out that there aren’t any goblins, but spider creatures called chitine instead Uncovered a chitine plot to start a war between the surface world and the drow Got convinced to try to stop that war Got trapped in the caves under the ruins Chased the chitine’s leader, a choldrith, further down into the cave system Nearly got crushed in a cave-in Fought your way through an undead infested mine Nearly got eaten by a colony of chitinous reptiles Picked up the choldrith’s trail and followed it deeper into the earth And now you stand at the entrance to a massive cavern filled with all manner of aggresive creatures. Yep, that about sums it up! And now, here you are, in this giant cavern thousands of feet beneath the surface. All you have to do is pick up that choldrith’s trail again, and manage to navigate the many factions vying for control of this little section of the Underdark. Good luck! And have fun storming the Hollows! This Gazetteer contains: Descriptions of the factions that live in The Shadowed Hollows, a massive cave complex far below the surface The underground city of Naakrasad and the important NPCs that live there Three quests leading to brief adventures within the Hollows for characters of level 4 to 6 7 custom maps of the Shadowed Hollows, Naakrasad, and the quest destinations All necessary monster stat blocks Everything needed to set the scene for the upcoming second chapter of the Into the Underdark Adventure Series