Mega-dungeon design made easy! The Oldskull Underworld Generator, Book I: Rats in the Walls features interlocking systems to generate all rooms, corridors, tricks, traps, lore, secrets, monsters, and treasure for level 1 of a gothic mega-dungeon, intended for adventurer experience levels 1 to 3.

Herein you will find an entire regional setting for a mysterious haunted castle, evoking the weird fiction of Dunsany, Grimm, Lovecraft, Howard, Machen, Merritt, and Perrault, alongside the classic dungeon design sensibilities of Arneson, Gygax, Holmes, and Moldvay.

Random tables allow for thematic generation of rooms, monster lairs, traps, tricks, treasures, and the prisoners in need of rescue. The author's bestselling systems from The Classic Dungeon Design Guides, the Oldskull Dungeon Generator, Castle Oldskull, Grimrook, Tyrrhenia, and the Realms of Entropy are distilled here into a lean yet richly detailed set of creation tools following the Moldvay/Cook Basic/Expert (BX) paradigm.

All of the in-depth history, secrets, mysterious rumors, and bestiary lore are laid out for you. Explore the ruined Exham Priory, now the Maw of the Skull, where monstrous rats scurry behind the walls, down through ghoulish sub-cellars, into the Haunted Kingdom of the Wererats, in search of the Majestic Domed City which crowns the Underworld.

This setting is home to Arthurian warriors and magi, Death Cults, Dunsanian gnoles, Gullygugs of Tsathoggua, Norvegian beast cult berserkers, Bwg-Bera bugbears, Lovecraftian daemon rats, Ghost-Slithes, Redcap creepers, Simonside Dvergar and Tomten, Shirelond halflings, elves of the Tylweth Teg, Old Guard Kloker kobolds, lizard men of Ba'al Molochai, mutoid Lubberkins, mycelians of the Seelie Court, grimalkin cats of Ulthar, Aklo undead, Orcneas of the Grendel Modor, Piskies of the Zoogs' Enchanted Wood, Bloody Bones undead, Hecatean Strixes, troglodytes of the Formless Spawn, and much more.

As the players' characters advance, they will descend from the Maw into the Ghoulish Crypts in search of imprisoned friends and family. These innocents have been stolen away by wererats to serve as sacrifices of blood and souls in order to awaken the Great Old Ones. What horrors of dream and madness rise, swirling down below?

The Oldskull Underworld Generator series can be used as a set of learning tools for Game Masters, as a prep tool (create an entire unique setting over a weekend for months of play), or as a solitaire storytelling and adventure system.
Rats in the Walls offers everything you need to begin. Every step of design is welcoming and guided. It is all included here, and it all works together. Another fine release from Kent David Kelly and Wonderland Imprints, Only the Finest Works of Fantasy. (64,500 words, 260 pages, in full color with 180+ graphics and illustrations.)