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

Deep beneath the Isle of Dread, in a place forgotten by the world of light, an ancient, unfathomable evil festers. Within the desiccated ruin known as Golsimorga, the debased kopru servants of Demogorgon work foul rites, steeping immature shadow pearls in pits of liquid insanity. None from the world above have yet fathomed what terrors lurk beneath the Isle of Dread, nor what mad scheme roils to profane life deep within the city's gangrenous corpse. "The Lightless Depths" is the sixth chapter of the Savage Tides Adventure Path, a complete campaign consisting of 12 adventures appearing in Dungeon magazine. For additional aid in running this campaign, check out Dragon magazine's monthly "Savage Tidings" articles, a series that helps players and DMs prepare for and expand upon the campaign. Issue #353 of Dragon features ways to improve the PCs' vessel, the Sea Wyvern, as they take their adventures back to the seas. When the PCs journey deep under the Isle of Dread to find the source of the shadow pearls, they discover horrors beyond imagining in a haunted underground city perched on sanity's razored edge. Pgs. 28-66

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

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

Rumors of faceless demonic creatures have been steadily rising in the Hillsfar region, and it is said that far below the surface of Faerun, nestled in the bowels of the Underdark, ancient terrors are stirring. The imperiled drow of Szith Morcane have extended an intriguing offer, but can the drow be trusted, and for how long? An eight-hour adventure for 11th-16th level characters.

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

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)

"Imperial Ghoul Outpost" is an iron ghoul lair suitable for four or five 10th-level characters. This adventure can be completed in a single session. When a clan of duergar prospectors unearthed caverns not on the their maps, they were particularly excited about a strange new iron orc they found there. not long after mining began, undead horrors emerged to attack the dwarves. Only one duergar escaped, his mind shattered by the experience. The Ghoul Imperium continues to explore the area, and it has its own plans for the newly discovered one.

Under the Flooded Forest grows a toxic maze of magical fungi called the Nidus. From this horrid realm a cult has struck a terrible blow against the wood elves struggling to regrow the trees in the forsaken swamp of the Flooded Forest. The elves, on the brink of extinction, need the adventurers to navigate this deadly labyrinth and recover a precious object. But the tunnels here crawl with spore-laden beasts and demons, and the very air itself is poisonous.

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!

The mine has been known as Tessount’s Folly for years, due to it producing nothing of value. Now Valmour, the youngest son of the mine’s late owner, has inherited the mine...and found something he should have left buried. Pgs. 56-81

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?

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

More than a hundred years ago, Delbera Axebringer—a mighty warrior and dwarven leader—slew the necromancer Audalot Karexin, but spared his young apprentice Zohir. In the ensuing decades, the bitter survivor brooded and plotted her revenge. Now, descendants of the Axebringer clan are vanishing, dragged screaming into the darkness by the animated bodies of their fallen kin. The Axebringers and their hometown of Davarn need heroes to break this family curse. What mysteries lie sealed within Delbera Axebringer’s ancient abandoned fortress? And what challenges lurk along the Blighted Path winding through the Darklands beneath Golarion’s surface? Down the Blighted Path is a deluxe adventure for 5th-level characters, and includes 64 action-packed pages of exciting battles, supernatural mysteries, and monstrous foes, plus a gorgeous double-sided poster map featuring an overview of the dwarven trading post of Davarn and a miniatures-scale battlemap! The author of this adventure, Monica Marlowe, was the winner of the 2015 RPG Superstar contest, in which hundreds of unpublished authors competed or the chance to write a Pathfinder Module. In addition to her adventure, this book contains a host of new monsters and magic items designed by the contest’s runners-up. Players can expect to reach 7th level upon completion of this adventure—if they can survive its deadly haunts, Darklands horrors, and furious villains both living and undead!

In the fourth installment of the Into the Underdark adventure series, characters come face to face with the heretofor unseen puppet master behind most of the strife and chaos in the Shadowed Hallows, Gyldrith the Chosen, a dreaded deep dragon! Includes: Three all new maps of Gyldrith's lair, and those of her minions Two all new monsters, the Ancient Deep Dragon and her Warlock of the Deep Dragon A new player option, the Deep Dragon patron for the Warlock Class. Unnumbered maps suitable for use in your favorite VTT Continues the story from Into the Underdark Part 1 - The Descent with areas and NPCs from The Shadowed Hollows Gazetteer

Eons ago, the demon lord Shomarrah defamed Lolth the Spider Queen, condemning herself into the cursed life of a massive purple worm. Now Shomarrah's desecrated body serves as a drow fortress, guarded by a mad sorcerer and his team of driders. What deeper evils lie within? "The Fasting Worm at the Spider Feast" is a Dungeons and Dragons 5th Editionmodule for a party of 3-5 players at level 8. This one-shot module is perfect for introducing your party to the Underdark and drow society, featuring a dungeon dive through a demon lord's snake-like carcass. Clerics in the party, upon completing the adventure, will be able to obtain access to the Feast domain. Details are provided at the end of the module

TENTACLES. VERY DANGEROUS. YOU GO FIRST. Adventure in the Underdark, Part Two The colony of svirfneblin, while grateful for the adventurers’ deeds, is still in need of a reliable source of drinking water. The kuo-toa hold the lake, and there is the matter of the tentacled menace the party faced previously… This adventure is a continuation of Tentacles. Why Did It Have to Be Tentacles?, but can be run by itself as well. It is designed to easily fit into any standard fantasy setting. A 4-hour adventure for 6th-8th 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.

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.

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