Dark Water Trap is a mini-adventure that has a single encounter that involves Duergar using darkness and anti-darkvision to get the player to fall into a Pit trap full of water, so that the party will drown. The encounter either works as a standalone (Ie. the Duergar have been causing trouble), or as a part of a larger adventure or dungeon, Duegar or otherwise. Pgs. 26-27

Side-Trek adventure When your PCs gain access to the teleport spell, their whole world changes. That simple spell opens up instantaneous, long-distance travel. No more long overland journeys or dangerous retreats through hostile territory. All it takes is clasped hands and a word from the wizard, and poof! The PCs are where they want to go. Except that it isn’t that simple, because teleport isn’t foolproof. The off-target teleports are a matter of scattering your PCs someplace else on the map and forcing them to get their bearings and make the long overland journey anyway. But this Side Trek focuses on the really intriguing column on the teleport chart: “similar area.”

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

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.

Undermountain: The Caverns of the Many-Legged is an adventure detailing a hidden mini-level for Dungeon of the Mad Mage for characters of levels 12-13. It uses some of the story and lore of that book, but it can be incorporated or dropped into any setting or homebrew campaign. In a hidden part of Undermountain, former slaves feed their fat, monstrous queen who is fixated on revenge. A broken drow house has finally found a place to call home – only to become abominations. And a massive beast slithers, hunting for anything to satiate its hunger and quell its madness. Welcome to the Caverns of the Many-Legged. Which side, if any, will adventurers choose as they explore this hidden mini-level for Dungeon of the Mad Mage? In this adventure, you will find: a mini-level that can be easily incorporated into Dungeon of the Mad Mage a vivid cast of unique monsters and NPCs, including chitine warriors, a choldrith queen, a spellcasting draegloth, a mad yuan-ti anathema, and others (stat blocks provided for all creatures not in the Monster Manual) locations that could be used or adapted elsewhere, such as a chitine colony and a drider-controlled drow fortress a combination of roleplay, exploration, and combat encounters

The Red Plumes have increased patrols in the region surrounding Hillsfar, and a string of disappearances has followed in their wake. Naturally, this has roused the suspicion of the factions. Join your factions and find out the truth behind the missing farmers. A four-hour adventure for 1st-4th level characters.

The Nexus spore is an intriguing Underdark adventure that can be sewn into any subterranean setting. This one-shot production was designed with long campaigns in mind, for when you want to break up the narrative to keep things fresh and interesting. This short adventure is ideal for players of level 5-7, although, much like the length of the adventure, it is easy to adjust. The adventure fits well into a single long session, or 2-3 short sessions. It comes complete with maps, stat blocks, boxed descriptions and a rare magic item.

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.

Sekarvu is a typical beholder. It spent much of its youth exploring underground realms and killing everything it found. One day, it came upon a large cavern filled with violet fungi. At the edge of the cavern, it found a small band of adventurers who had all but succumbed to the toxins of the fungi's tendrils. They offered little resistance to Sekarvu as it approached and began to feed on their still-writhing bodies. With its first bite, the beholder's life changed forever. Pgs. 52-55

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.

A Beholder Love Story A dwarven mineshaft has become the new home of the heartbroken beholder Sindryl. Discover who could be wicked enough to separate Sindryl from his love Prix'am, put a stop to their plot, and restore Prix'am's missing heart. A 3-6 hour Dungeons & Dragons 5th Edition adventure for Tier 2 characters. This adventure includes: 2 New Monsters (including 1 New Beholder!), 3 New Magic Items, New NPCs, a Minecart Skill Challenge, Romantic Random Encounters for the Underdark!

If absolute power corrupts absolutely, Matron Maelora best beware; her plans for total domination of the Underworld are already close to satisfactory completion, while attacks on the Upperworld have become increasingly successful. The other power-hungry drow families of Holoth may despise her but they know a true leader when they see one, and House Gullion has been revealed as the family to lead them all on the path to glory. With the entire Underworld in chaos and the Spider Goddess regularly communing with her chosen Matron, far greater dreams than mere regional conquest are within the grasp of the drow, as Maelora prepares her grand dark elf army for victory! With other mystical allies standing firm with the Matron, other Underworld races beneath her heel or cowering behind fortified walls, and every drow ready to play their part when she gives the word, what could possibly stop her from achieving her final triumph and fulfilling her destiny? But even the greatest of plans has a flaw if you look hard enough, and a party of stout heart and strong resolve can make a difference. At first, such a party may well believe it is on a smaller adventure, perhaps to win a few baubles or some small acclaim by rescuing a few kidnapped villagers. Soon, however, those adventurers will realise that much more is at stake, and that they are the ones who will need to make moves against the evil Matron Maelora and her increasing dominance if both the entire Underworld and Upperworld are to be saved. But how will they go about it? Can they ensure their own success when an entire city is standing against them? Only they have the chance to halt the Rise of the Drow! Published by AAW Games.

When the PCs stumble into the Feywild, they find themselves in the middle of Mithrendain— a glorious eladrin city of grace and beauty. But as the heroes find themselves the target of mysterious attacks, they begin to discover that something rotten lurks in the city’s heart. Sunlight bathes the soaring towers of the eladrin city of Mithrendain. Gentle breezes swirl through wooded parks and along well-kept streets, and in the ancient settlement whos golden hues have seen it named the Autumn City, thousands live in peace and prosperity. For centuries, the fomorian chasms deep beneath the city have stood silent below the great magical seals that closed them in the wanting days of the eladrin empire. Over long years, the folk of Mithrendain have forgotten the dark threats of old, becoming complacent in their tranquility. And so none suspect that corruption lurks at the heart of the city, spreading out from the shadows to taint all it touches. Pgs. 104-128

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

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

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 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.

Gyldrith the Great is coming, and she is not happy. How long have you been down in these caves? Days? Weeks? More? Time is hard to track this far underground. And so much has happened since you descended into the tunnels beneath Dhonin’s Lookout. Now, you stand guard at the Great Gate of Naakrasad. Exhausted from your past battles, and your narrow escape from the cat and mouse games of the ancient deep dragon, Gyldrith. You can hear the hoots and hollers of her horde of bloodthirsty minions just beyond the city walls. A battle is coming, a battle against great odds. A battle that will test your mettle like none before. And you wonder if you are up to the task. A massive battle ranging across the small city of Naakrasad in the Underdark. Giant map of the city of Naakrasad with close-up details of the major battle sites in the adventure. Several new monsters, including the vicious Half-Ogre Hound Master and his deadly Hell Hound pets. Unnumbered maps, including the entire city of Naakrasad, to use in your favorite VTT.

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!

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!