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

Part megadungeon, part underground expedition, Operation Unfathomable serves as both a one-shot adventure and a campaign framework. PCs are (optionally) drafted at swordpoint to recover the Nul Rod, a priceless artifact that was recently lost in a local prince's foolhardy attempt to destroy the Chaos Gods of the Underworld. The PCs have been drafted as an expendable set of pawns to venture into the vast and bewildering Underworld and retrieve the Nul Rod. With the Underworld's innumerable beasties being on high alert after the prince's expedition, the PCs must sneak through the incredibly dangerous Underworld. Fighting is not as important as stealth, fast-talking, and running away rapidly. This is the expansion from Sholtis's original Operation Unfathomable, released in Knockspell #5 (2011).

From the magazine: "The monster you're sent out after is so dangerous that even mind flayers fear it. And the illithids want your help!" Earthquakes hit the area around Needlespire mountain, affecting both dwarven and deep gnome villages, and the local mining industry. Deep gnome expeditions discover an illithid outpost! This adventure includes roleplaying encounters with both deep gnomes and illithid in their quest for the true cause of the earthquakes. The creature causing the earthquakes is a draknor which has sent its huge tentacles into the earth seeking magma to fuel its growth. Pgs. 38-60

The gnome village of Clefton is built on the sides of a deep gorge, their homes built safely into the gorge walls. But for the past two nights Clefton has suffered the attacks of sightless creatures that crawl down the walls and steal away the gnomes’ loved ones. It’s up to the PCs to follow the creatures’ trail back to The Draigesgyrn Caves and put an end to their threat. As the PCs explore the unusual cave complex, they may discover the caves are the empty husk of a colossal dragon, buried many years ago beneath a landslide. In the depths of these caves they encounter the dread spirit of the dragon rider and an entrance to the Underdark. Will they seal the entrance or will they begin a new adventure deep underground? The Draigesgyrn Caves is a D&D 5th Edition adventure suitable for four to five PCs of 5th level and estimated to take 4-6 hours. The adventure could be set in any mountainous area. In the Forgotten Realms, it might be set in the Fairheight Range on the Moonshae Isles. The end of the adventure introduces an option to begin an Underdark adventure or campaign. Includes: A map of the dragon husk caves by EB Moreno Two new monsters for 5th edition – the ghoulish ooze and a grimlock shaman Four new magic items

The Ghost Tribe of Orcs were driven from their home under Wyvern Tor by some terrible evil. They marched to Phandalin and attacked, only to be defeated. Now the heroes will go beneath Wyvern Tor to discover the terror that chased out the orcs and perhaps find the source of the orc’ssardonyx. Journey to Beneath Wyvern Tor is the third of four parts in the After Lost Mine series. It will play out the journey to the orc’s former cave settlement and then into the darkness beneath. Part IV will have the party deal with the terror from the Underdark that drove out the orcs.

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.

An unexpected envoy arrives in Sporedome and offers to give aid against the fire giants of Maerimydra, if you are willing to help his people with a small problem. A two-hour adventure for 5th through 10th level characters. Optimized for five 8th level characters.

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

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.

From the backcover: "Once a generation, they say, a strange comet appears in the sky overhead and the gates of Firestorm peak swing open, (twenty-seven years ago, your father led his band of adventurers into the mysterious mountain, never to return. Now the Dragon's Tear once more flickers in the sky, and the glass gates on the mountainside beckon. Will you pass through to discover the secrets that await beyond the portal none has ever dared and returned? The Gates of Firestorm Peak is the first adventure designed especially for use with the new rules presented in the three PLAYER'S OPTION books: Combat & Tactics, Skills & Powers, and Spells & Magic. While it can also be played using just the AD&D® game core rules (the Player's Handbook and the DUNGEON MASTER® Guide), this adventure offers a perfect opportunity to experience all the potential of the new optional rules. One of the highlights of this package is the first PLAYER'S OPTION player character record sheet. To meet the challenges of Firestorm Peak and escape with their lives, heroic adventurers must battle dark dwarves in their underground city, explore the abandoned caverns of the Elder Elves, and deal with weird alien entities from Beyond. Their goal is to stop the Master of the Twisted Caverns and his dark minions from completing his sinister plot before it's too late . . . if they can. Included in this product are a 96-page adventure book detailing the dungeon that lies beneath Firestorm Peak, 4 full-color poster maps detailing all the important locations in the complex, and a sheet of 56 counters for use with the tactical maps in major combats."

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

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

Recent earthquakes have unearthed a small section of a lost dwarven fortress. The dwarves are long gone, but rumors suggest they might have left treasure or weapons behind. After a journey into the Underdark, the characters find a barred iron door bearing the names of several ancient dwarven clans. Pgs. 90-95

A 20-page adventure for OSE Save the wizard! A sunken cathedral on a quiet mountain lake hides a long forgotten temple to Mathanoga, God of Knowledge and wizardry. Abandoned by Man for centuries , but protected by the legend of man-eating fishmen lurking in it. Or until a few weeks ago the young wizad Elric embarked on its expedition. With help from the accademy of Greykeep he found the temple and began to explore it, hoping to uncover its ancient magical secrets. Now the wizard is missing and the accademy has put a bounty on its head: its weight in silver to whoever will find him and bring him home alive and well. Find magical secrets! Deep inside the temple are stashed many magical items, all sacred to the fishmen dwelling there, all worth dying for. Save Elric and the treasures will be yours! The Sunken Temple is an expert level Old School Essentials adventure for a party of 1-4 players. Perfect for a one shot or a random encounter in an hex crawl.

Peren, a guildless Devkarin collector of obscure relics has gone missing. The elf of shadow is in deep debt to the Orzhov as well as to the Rakdos performer, Ophyira. To discover Peren’s fate the party must descend into the Undercity of District Four, within the territory of the Golgari Swarm. Continuing the story which began with Off to a Weird Start, and picking up where The Palace of Pain’s Pleasures left off, this adventure is designed to be part of an ongoing campaign. For Dungeon Masters who wish to incorporate The Felicity Triskelion independently from the ongoing story, 10 Adventure Hooks (one for each guild) are included, giving The Felicity Triskelion flexibility for one-shot play or for inclusion in your own campaign!

"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.

What elder evils lurk in the depths of the freezing mountain ruins? Find out in The Stoneheart Ruin! The adventure features: An adventure set in a desolate, wintry mountain landscape. 16 pages full of intrigue and mystery, containing full color maps, plus 2 unique monster stat blocks. Provides a great introduction to Mind Flayer lore and mythos for Tier 1 players. Can easily be set in the Spine of the World for use in Rime of the Frostmaiden. Let your characters test their mettle as they climb and face the ancient dangers lurking in the cracks of The Stoneheart Ruin! “I have no explanation for any of these finds. We heard disturbing noises coming from further within the mountain; thunderous and growling.” Excerpt from a pamphlet, signed: “Koralia Meadring, Anthropologist Extraordinaire” Koralia needs you to investigate her most recent discovery: a ruined cavern deep in the mountains. Her small team of academics did a cursory walk-through and think they've found a big breakthrough! However, they left in a hurry after being frightened by the horrors they heard coming from deeper in the mountain. They escaped and found one of their team was missing - a goliath named Marek. You must climb the mountains and locate the ruin, make certain that it is safe for study by Koralia’s team, and if possible, find and rescue Marek, whose fate is uncertain. Made during the November 2020 RPG Writer's Workshop.

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.

"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 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!