Monday, March 24, 2014

Notes on the The Codex of Dungeons

Of my three OSR Superstar entries, the Codex was the only one I came up with that week and specifically for the contest. I spent several days thinking about entries, and came up with several criteria I thought a good item, and entry, should meet.

  1. It should be usable by a broad range of characters, not just fighters or name-level.
  2. It should help the characters. If it wasn't of benefit, they wouldn't use it.
  3. It should also have a cost. This makes things interesting, because the benefit has to be worth the risk.
  4. It should engender adventures. All magic items can be given stories, but some naturally lead into adventure. A sword +1 is static; a deck of many things is not.
  5. It had to be unscripted enough for a DM to want to use it. 
Ultimately, what kept popping into my head was book of maps. They'd be accurate enough to be useful, but not so accurate that the party could bypass all the traps, find all the secret doors, and avoid all the monsters. Having the book magically transport the characters to and from the dungeon, but only once, allows a party access to a large number of dungeons but creates a risk of being stranded (if their page is stolen), involuntarily returned home (page fails its save vs dragon fire), and gives them incentive to make an overland connection between "base" and the dungeon if they want to return for any reason (hex crawl!). Researching the dungeons in the Codex to locate them in the real world brings the party into contact with sages, seers, and all sorts of NPCs.

The one-way flip through the book puts pressure on the party to utilize it; they can't pick and choose at their pleasure, and the dungeons get harder as they go. The party gets the most benefit from the book if they use it early and often. It works for 1st-level parties just as well as 8th-level ones.

Since the dungeons aren't scripted, the DM can choose what to make available, and because the information in the book is unreliable, the DM doesn't have to give away the good stuff. Maps are easily obtained, from random dungeon generators or the website of your choice (I'll put up links tomorrow).

The master map, of course, is the ultimate threat and potentially the great reward . Dumped in an unknown dungeon, unprepared. No map, only half your gear, and three random tavern patrons sucked along for the ride. Ready for it?

Codex of Dungeons: The Codex of Dungeons is an unassuming tome, bound in leather with tarnished silver clasps. It feels lighter than it looks, and opens easily, almost willingly.

Each page of the Codex bears the name of a dungeon, a map, and a few jotted notes and sketches. A few of the dungeons may be familiar to adventurers, but most are unknown. The maps are fairly uniform in size and scale: some display the entirety of a small dungeon; other maps are clearly subsections of larger complexes.

The notes are written in same hand throughout the Codex. Some indicate traps; others show likely guard positions, barriers, or entrances to passages not indicated on the map. A few indicate treasure. The sketches depict a variety of features: doorways, arches, columns, reliefs, and so forth.

The first time the Codex is opened with an intent to study it, it opens to the first page. The book may be closed and opened any number of times thereafter, but it always opens to the same page. The pages flip stiffly and with great difficulty, and only one at a time. Once a page is flipped, it cannot be opened again – the dungeon depicted is no longer accessible via the codex.

Tearing a page from the book transports the tearer and anyone around them to the entrance of the dungeon depicted on the page. Adventurers exploring the dungeon will find the map’s directions reasonably (~75%) accurate but incomplete: no more than one or two traps are usually indicated, for instance, even if the dungeon holds many more than that. Inhabitants, treasure, and other features are similar: a dungeon may hold goblins as its primary inhabitants as written, but they are allied with ogres instead of gnolls, and keep a cave bear instead of hyenas.

Burning the torn page returns everyone who was transported to the dungeon back to the point of origin (where the book was when the page was torn out). Corpses and the like typically return as well, unless they were consumed, cremated, or otherwise destroyed. The Codex can be opened and have multiple pages torn out (individually, not as a group), transporting characters to a variety of dungeons and back again (clever characters might use this to their advantage, or find themselves leaving the frying pan for the fire).

The dungeons become progressively more dangerous as the pages are turned, so characters that frequently flip pages will rapidly find themselves over their heads. (assume 1d4+2 dungeons per party level, beginning with dungeons suitable for 1st-level characters, then 2nd-level characters, and so forth). The total number of dungeons listed in the Codex of Dungeons is unknown, but may be beyond number. Many of the more dangerous and fantastic dungeons are rumored to be on different planes of existence altogether.

Finally, there is a danger to the book not revealed by any form of divination magic. Each time the Codex is opened, there is a 5% chance that it reveals the master map. This map can be unfolded to reveal a vast, sprawling dungeon labyrinth that seemingly includes every dungeon portrayed in the Codex. One minute after the master map is unfolded, however, everyone in the area is transported to the master dungeon, and the Codex and any of its torn pages disappear from their possession.


  1. Yep this is brilliant and very springboard-to-action -- the freedom created by the book to go to these remote locales is limited by the one-shot nature of the book's magic. Plays right into the hands of the DM who is ready for a change of scenery.

    1. Thanks! And yeah, a very meta- part of me was thinking "how do you get a party to all these one-page dungeons and stuff without putting them in Undermountain, Myth Drannor, or the granddaddy, Castle Greyhawk? How do I use all these maps?"