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

Detailed encounter, easily convertible into an adventure. Starts from investigating ambushes on the mountain pass and quickly escalated into a more twisted story about duergars, alhoons, and treasure vaults. Setting-agnostic (classic fantasy - best)

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but are the fishy folk really the ones to blame for leaving the gem-loving svirfneblin thirsty?… This adventure was originally made for a West Marches campaign, but is designed to easily fit into any standard fantasy setting.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

The Borderlands. An untamed wild region far flung from the comforts and protection of civilization. A lone fortified Keep is the only bastion of Good desperately striving to maintain the forces of Chaos at bay. But Evil is everywhere, lurking in dark caves, fetid swamps, forlorn forests. Bands of cutthroat brigands and ruthless tribes of humanoids eager to clash with the forces of Food rove the region. The Borderlands hold many secret wondrous locations, and opportunities for fame, prestige, and fortune are plentiful. But equally abundant are the perils, risks, and challenges to those brave enough to explore the wilds. Sharpen your swords and axes. Purchase your iron rations and tinderboxes. And Don't forget at least one 10-foot pole. Adventure awaits those with the mettle to confront Chaos in the Borderlands!

The Case of the Kidnapped Cartographer A dear friend of the party has gone missing; Boddyknock the gnome cartographer, supplier of maps and charting equipment. Can the party solve the mystery of his disappearance? Do they have the bravery to delve deep to recover their lost ally? What horrors will they uncover in the cavernous expanse beneath their feet?

Are your player's going fishing in the Underdark? Booked a ride with the Kua Toa Travel Agency? Taking a cruise on the Darklake? Well then Journey Through the Center of the Underdark 2 - The Darklake Strikes Back is just what the Leemooggoogon ordered! Like the first Journey, The Darklake Strikes Back contains several encounters designed with Out of the Abyss traveling days in mind, but easily inserted into any 5th Edition Dungeons & Dragons Underdark setting. Unlike the first Journey, The Darklake Strikes Back has a mid sized three level dynamically defended dungeon, complete with a dragon at the bottom! This complex is right at home on the Darklake but could also readily be inserted into your Tyranny of Dragons campaign as well. Written for a party of characters levels 4-6 with notes included for adjusting encounter difficulties for lower or higher level groups Journey Through the Center of the Underdark 2 - The Darklake Strikes Back should provide 6-10 hours of gameplay excitement!

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.

"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 module takes place in a large cavern that is part of an extensive underground cave network. It can be used as a side-trek encounter in the Undermountain or Night Below campaign." -- from the adventure. Includes a small keyed map of the cavern.

The final confrontation with the giant, King Snurre, and the entry of mighty adventurers into the caverns under his stronghold (DUNGEON MODULE G3, HALL OF THE FIRE GIANT KING) discovered the Dark Elves, the Drow, had instigated the giant alliance and its warfare upon mankind and its allied races. 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 cavern area, encounter and map matrix keys, and an additional section pertaining to a unique new creature 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 first part of a series of three modules (with SHRINE OF THE KUO-TOA, D2, and VAULT OF THE DROW, D3), or as the fourth part of a continuing series of modules which form a special progressive campaign scenario (DUNGEON MODULES G1, G2, G3, D1, D2, D3, and Q1, (QUEEN OF THE DEMONWEB PITS). TSR 9019

The Zhentarim ask the party to investigate what happened in one their most important underdark outposts. If the party accepts, they'll have to deal with maddening darkness, grimlocks, an insane kenku assassin and unpredictable mixtures of potions. A short, fun dungeon romp that is easily adapted to other settings and other patrons. The combination of utter darkness and a villain based on sound makes for fun shenanigans on the side of the DM. Feasible as a one shot for an efficient party. Two tendays ago, Zhentarim agents were to transport a shipment of rare potions between their Underdark outpost and the surface world. The shipment has yet to arrive, and the outpost is not responding to any sending spells. Growing worried, the outpost’s overseer sends a group of hireswords to investigate and return it to Zhentarim hands. This particular adventure deals with the delusions of madness of Fraz Urb'luu. It also features Muurmic, the mad kenku first described in the December 2015 issue of Dragon+.

Waves of supernatural darkness sweep over the subterranean city of Stoneholme, quenching lights and bringing with it foul creatures of shadow. After heroically defending a group of dwarven children being ravaged by a group of these shadow beings, the PCs are approached by Shtawn Deppenkhut -one of the king's own advisers- and are offered the task of finding the source of the darkness that threatens the city. The PCs investigation takes them through the Underworld to hidden caverns, where demon worshiping priests offer living sacrifices in an attempt to plunge Stoneholme into everlasting darkness, a first step in destroying the hated city once and for all, but as it turns out the priests aren't the only ones behind this unfolding plan to destroy Stoneholme. Dark Days in Stoneholme is ideally suited for a group of dwarven adventurers. It is recommended that you have access to the Stoneholme section of the Rise of the Drow revised & expanded edition (2014) but it is not necessary to run the adventure. Also available for Pathfinder. Published by AAW Games.

Expand your game with this collection of 56 NPCs of various Challenge Ratings, thirteen of which include maps and details of their lairs. Add these NPCs as a side-quest, a main villain, a one-shot, a bounty for easy money, or however else you wish. Written by some of the best-selling authors on the Dungeon Masters Guild and outstanding podcasters, each NPC includes an image, a backstory, motives, flaws, and a stat block. Some even include new magic items!

Hunt for a Legendary Treasure! Deep beneath a peaceful valley lies the vault of the legendary drow adventurer Larin Karr. Rumor has it Larin Karr has gone, but his vast treasure acquired from years of plundering hordes in the Underdark still remains. Can you find and loot the impenetrable vault? The Vault of Larin Karr details Quail Valley, its residents and monsters, and the twisting tunnels of the Underdark that stretch beneath it. The Vault of Larin Karr takes PCs from 4th to 9th level, during which time they fight dragons, find a missing statue for a band of renegade elves, save the village of Pembrose from scheming hobgoblins, and explore the Underdark and its many dungeons - including the legendary Vault itself! Contains new monsters and magic items! 2003 ENnie Award Silver Winner: Best Adventure

The Underdark holds many secrets. A series of earthquakes and eruptions have rocked a normally placid land. Strange creatures sighted in the dark of night raise fears across the already disturbed countryside. As tales of a lost race that once warred with the drow begin to surface, only the boldest adventurers dare to descend into the shadowy darkness.

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

Written by the setting’s creator, incomparable RPG author Monte Cook, Ptolus: Queen of Lies is an action-packed fantasy adventure painstakingly re-designed for Ptolus: Monte Cook’s City by the Spire. Involving numerous challenging scenarios for characters of 11th level, Queen of Lies is filled with dozens of dark elf personalities, cunningly showcasing their alien culture—a world of merciless betrayal and sinister lusts. Deep below the surface, in the sunless lands of the Netherdeep, creatures of darkness build weapons and amass armies, dreaming of invasion. An attack on a peaceful elven shrine in Emerald Hill sends the heroes on a quest to retrieve stolen artifacts and kidnapped friends. All signs point to the actions of the dark elves of Ul-Drakkan, far below the city of Ptolus. However, even within that ancient fortress, there exists a deeper darkness.... Underground enemies lurk beyond every twisting passage, and strange creatures abound. The foul culture of the dark elves is both decadent and cruel, and the heroes may discover that they’ve stumbled into a web of deceit and treachery spun by the self-styled queen of the dark elves. Can the player characters complete their mission without being discovered, or will they find out, perhaps too late, that their actions been orchestrated all along by the wicked Queen of Lies? Published by Fiery Dragon Productions

Troubles simply mushroom in the Underdark. The alchemist would like some fungus and spores, but no one wants to get them. Perhaps you could help. The adventure begins with the party finding a caravan. In addition to being able to trade with these NPCs, the party also can be hired by an alchemist to bring bag some red fungus and some Myconid spores from underground. Underground, the party will have a chance to interact with friendly Myconids and venture through a large labyrinth of passages (this labyrinth isn't mapped and is dealt with through storytelling, random encounters, and roleplay). The adventure culminates in a battle between the Myconids and Flinds, and the players can participate. Pgs. 4-12

The waters of a sunless sea meet a pebble-strewn shore, beyond which opens a wide Underdark vista shimmering with pale cave-light. Titanic columns as big as castles march miles into the misted distance. The wide, steeply sloping base of the nearest colossal column is carved with streets, walls, and elaborate structures, many with gaping, empty windows. A few glimmer with faint illumination. Are you brave enough to explore the spire-city and face the terrors that lurk within? Part 2 of the Barrow of the Forgotten King series. Followed by Fortress of the Yuan-ti.

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