From publisher blurb:
In His Majesty the Worm, characters adventure through a mythic underworld underneath the city at the center of the Wide World.
In the same way that a hobbit hole is different from a nasty, dirty, wet hole, the mythic underworld is different from a simple dungeon. It’s not merely a cave system with kobolds and goblins hiding in every shadowy corner. It’s another world, charged with unconventional physics, inhuman entities, and alien architectures.
As a gamemaster, creating a mythic underworld can seem daunting, but it’s really just a series of small, discrete tasks.
Break a megadungeon down to its atomic constituent parts.
Populate it with interesting things.
Connect these levels together.
It’s less making one huge megadungeon and more creating several, smaller dungeons and creating an appropriate flow between them.
This book contains a procedure for laying out interconnected dungeons, as well as inspirational dungeon seeds to use as prompts. Because His Majesty the Worm is not a premade setting, the descriptions of the seeds are just suggestions—meant to be evocative. For each seed, we’ve included a map from Dyson Logos. You can use this map or make one of your own using the procedures in this book.
By following through the atomized steps, you’ll have a working mythic underworld with a few hours of work.
This book contains:
A procedure for laying out a Jayquayed megadungeon layout
Twenty-one inspirational dungeon ideas with maps
Dungeon checklist that encourages meaningful exploration
Procedures for making maps, keying rooms, and making random encounter tables
Thorough walkthrough of making a dungeon level