OSR / Dungeons & Dragons 5th Edition Adventure by Old School Dungeon Master
The Haunted Keep
An old-school dungeon adventure inspired by the Moldvay Basic Edition—playable with dice, pencil, and paper.
The Haunted Keep is a complete one-shot adventure for old-school fantasy RPGs, reimagining and expanding upon the legendary “Haunted Keep” example from the 1981 Basic Set. Designed for use with any OSR or 5e-style ruleset, this adventure includes maps, keys, NPCs, treasures, and monsters—everything a Dungeon Master needs to bring the ruined fortress of the Odemus family to life.
Once a proud castle, the keep has long fallen into ruin. Strange lights now flicker from its broken towers, and villagers whisper of cries echoing through the night. Unknown to the outside world, the cursed Odemus family still dwells below, their bloodline transformed into a sinister clan of wererats commanding a host of goblins from the caverns beneath the fortress.
The heroes’ journey begins with a desperate rescue: villagers have been kidnapped by goblin raiders and taken to the ruins of the keep. But as the adventurers delve deeper, they uncover the grim truth—that something far more dangerous than goblins lurks below the crumbling gate towers.
Inside this book you’ll find:
- A fully mapped three-level adventure:
- Explore the ruined towers, crypts, and caverns beneath the ancient Odemus stronghold, featuring 30+ keyed encounter areas filled with traps, treasure, and lurking horrors.
- The Odemus Family of Wererats:
- Eight unique NPCs with stats, personalities, and motivations that drive the adventure’s central mystery. Each encounter reveals new threads of the family’s dark lineage.
- Goblin Warband Command Structure:
- Tables and guidance for running Grok’s goblin forces, their patrol routes, and their uneasy alliance with the Odemus clan.
- Random Encounter & Event Tables:
- Easily adaptable for OSR or 5e systems, these tables allow DMs to customize encounters, room occupants, and rat infestations throughout the dungeon.
- Dungeon Design & Narrative Notes:
- A detailed DM section explaining the keep’s history, the lycanthropic curse, and how to weave the goblin raids and wererat schemes into your ongoing campaign.
- Multiple Play Options:
- Play as a three-session arc (rescue, raid, and reckoning) or run as a marathon delve into the depths of the Odemus warrens. The modular design supports both structured and open-ended playstyles.
Adventure Summary
The party’s mission begins with the abduction of villagers from Blaize. Sent by Sir Robert, the heroes must infiltrate the ruined keep, confront Grok’s goblins, and rescue the captives. But deeper below, the Odemus family plots to reclaim their ancestral lands through blood and dark magic. The final confrontation in the family’s subterranean temple may decide the fate of the region.
Whether you’re a veteran Dungeon Master seeking a nostalgic return to the magenta-box era or a new DM looking for a complete, ready-to-play adventure, The Haunted Keep delivers everything you need to run a night of classic dungeon crawling and gothic intrigue.
Gather your courage, light your torches, and enter the ruin where the Odemus curse endures. The Haunted Keep awaits.
The Haunted Keep is available through DriveThruRPG in Print and PDF.
Please note: The links in the post above are “affiliate links”. This means if you click on the link and purchase the item the author of this post will receive an affiliate commission.
Voices From The Pulpit 