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 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

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?

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.

Save the village of Millvein! Prevent a war with the drow! In this 3-4 hour adventure for 4-5 characters of 2nd level, travel to a small chitine lair to prevent them from destroying the small village of Millvein and inciting a war between the surface and the drow. Includes: A 3-4 hour adventure for 2nd level characters Map of the village of Millvein 2 DM maps Stat blocks for all monsters the players might encounter. See where the adventure began in Into the Underdark - Part 1 A Family Affair The adventure continues in Into the Underdark - Part 3 They Call It A Mine

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

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

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.

Tieflings are raiding a dwarven expedition under a shield of magical darkness, but if the PCs can supply the dwarves with giant scarab beetles capable of generating potent bursts of magical light, they might just survive. Unfortunately, they'll need to escort the herd of giant beetles through the Underdark first. A D&D adventure for 3rd-level characters.

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.

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.

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.

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!

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)

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.

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

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

Far below the Fields of Petrichor is a vast cavern containing the skeletal remains of a long-dead Sonorous Titan, a whale-like beast that once floated through the skies of a lost age. Amongst the bones are ravines and grottos home to bizarre creatures and lost treasures that are as beautiful and valuable as they are deadly. Ghostly shapes swim through the air. Glowing mushroom groves hide frightened creatures. And the Titan’s bones sing sadly as an ambitious wizard and his weary hirelings dig for its precious marrow... ADVENTURE TYPE: Small Sandbox Dungeon DESIGN NOTES: This adventure is intended for characters levels 5 to 8. It includes several wilderness areas, a ruined village and a mining camp to explore. Each area contains various encounters and unique magical items.There are many opportunities for combat, but it is possible for players to explore most areas and complete many interactions without any combat at all, depending on their choices. INCLUDES: Story hooks, dialogue prompts, creature stat blocks, original creatures and treasures, and dungeon overview map. KEYWORDS: Grave, skeleton, ghost, undead, wizard, miner, puzzle, mushroom, myconid, hag, witch, social, curse, mutation, mutant, soul, insect, termite, scorpion, bat, monk, beetle, chicken

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.

"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.