Friday, 28 August 2020

Stocking dungeons with one die roll

Some History

In OD&D, Gygax lays out his procedure for randomly stocking a dungeon in "Section 8: Referee Information," beginning on page 68 (Single Volume Edition from 2011). 

  • "Thoughtfully place several of the most important treasures, with or without monstrous guardians."
  • Roll 1d6 for each remaining room: 1-2 indicates a monster.
  • Roll 1d6 for all rooms again: 1-3 on "those rooms or spaces with monsters in them indicates some form of treasure is present." A 1 on a "room or space which is unoccupied indicates that there is some form of treasure there."
He then provides monster tables for stocking level-appropriate monsters, and treasure tables for level-appropriate treasure. To me, this procedure feels a bit clunky because of the multiple die rolls. The percentages don't map out exactly to any standard die sizes. 

Result (d6)%total
1. Monster16.67%33.33%
2. Monster16.67%-
3. Empty16.67%66.67%
4. Empty16.67%-
5. Empty16.67%-
6. Empty16.67%-

But with a little difference it can be mapped to a d10. 

Result (d10)%total
1. Monster10.00%30.00%
2. Monster10.00%-
3. Monster w/ Treasure10.00%-
4. Monster w/ Treasure10.00%-
5. Empty10.00%60.00%
6. Empty10.00%-
7. Empty10.00%-
8. Empty10.00%-
9. Empty10.00%-
10. Empty w/ Treasure10.00%-

So we have some appropriate treasures and monsters placed by the referee, and then 50% of remaining rooms are "empty." Overall we have two-thirds or 66% of all rooms empty (aside from the ones placed by the referee at the beginning). This feels like a lot of empty rooms. I know that "empty" doesn't necessarily mean EMPTY, it simply means no monster, no treasure, no traps, and no special things. Courtney Campbell's On Tricks, Empty Rooms, and Basic Trap Design is a brilliant reference to make your "empty" rooms shine. They don't have to be boring. But they're not very interactive. And interactivity is fun. 

The procedure was simplified to a single roll in some later editions. In the 1st Edition AD&D Dungeon Master's Guide (pg. 171), we find this table:

Table V. F.: Chamber or Room Contents
1-12 Empty
13-14 Monster Only
15-17 Monster and Treasure
18 Special
19 Trick/Trap
20 Treasure

This simplifies the stocking procedure to one die roll. This method provides 60% of all rooms to be "empty." So slightly fewer empty rooms than before. But we also see the addition of "Special" and "Trick." Not sure what exactly that might mean to all referees, but I sure do like the idea of "Special." Special can be anything I want. Extra creatures, something weird to play with, inspiration to add something odd and wonderful. 

In 1981 Moldvay Cook Dungeons & Dragons Basic Set (page B52) we find these tables:

First Roll: CONTENTS
1-2. Monster
3. Trap
4. Special
5-6. Empty. 

Second Roll: TREASURE?
1. Monster = yes. Trap = yes. Empty = yes. 
2. Monster = yes. Trap = yes. Empty = no. 
3. Monster = yes. Trap = no. Empty = no. 
4-6. Monster = no. Trap = no. Empty = no. 

Here are the percentages:

4Monster w/ Treasure5.56%16.67%
5Monster w/ Treasure5.56%
6Monster w/ Treasure5.56%
9Trap w/ Treasure5.56%5.56%
18Empty w/ Treasure5.56%5.56%

With a little tweaking this can be mapped to a d20. 

5Monster w/ Treasure5.00%15.00%
6Monster w/ Treasure5.00%-
7Monster w/ Treasure5.00%-
10Trap w/ Treasure5.00%5.00%
19Empty w/ Treasure5.00%10.00%
20Empty w/ Treasure5.00%-

If we write it out in the same format as the 1st Edition AD&D table, we see some differences. 

Chamber or Room Contents
1-5 Empty
6-9 Monster Only
10-12 Monster and Treasure
13-14 Trap
15 Trap and Treasure
16-18 Special
19-20 Treasure

Now we only have 25% of rooms truly empty. That's way less. And now it feels like too few maybe? I'm not sure. Older editions of D&D really seemed to love the d6. Maybe because it's common and familiar. They seem equally fond of the d20. Excellent spread, I'll admit. We all have personal feelings of different dice and their combinations. 

My Dungeon Stocking Die

For my personal use, I decided to go with the d12. This allowed me to still work with the common fractions from the d6, i.e. 25%, 33.33%, and 50%. I kept Special but I dropped Trick. I also like to use the term "Creature" rather than "Monster" because I feel like it encompasses more, like neutral factions and potential allies. 

Linden's Dungeon Room Content Die
1-4. Empty
5-6. Creature
7-8. Creature with Treasure
9-10. Trap
11. Special
12. Special with Treasure

I love this d12 I have from Chessex. 

And here are the percentages:

Result (d12)%total
7Creature w/ Treasure8.33%16.67%
8Creature w/ Treasure8.33%-
12Special w/ Treasure8.33%8.33%

I ended up with 33.3% of rooms being empty. This feels like a good point for me. Enough to make dungeons feel expansive and realistic (why are there goblins in every single room?), while not having too much empty space with no interactivity. On average, the party should travel through no more than two empty rooms in a row before stumbling across something fun. That feels good to me. 

I also like having very populated dungeons, so fitting Creatures into 33.3% of rooms feels good too. In a similar figure, on average, players should get a break from social/combat encounters after no more than two rooms. 

I ended up putting two "Special" entries—one with Treasure and one without—because I love Special. If I'm keying a themed dungeon, this will often be something interesting to do with the theme. For example, in a seasonal-themed dungeon a room enchanted to have snow fall from the ceiling. Not quite empty, but also not really a Creature, Trap, or Treasure. It's something interesting, thematic, and interactive (snowball collection, source of clean water, etc.)

Something I'll have to decide about is the amount of Treasure. Is having Treasure in only 25% of rooms enough? I think it is, but maybe not. It will force me to make treasure caches a little bigger than others might. But I don't mind that. I'm not a fan of parties mowing through gnoll after gnoll simply to collect the 3cp per pocket that they can find. I'd rather slog through nine treasure-less rooms and finally end up with a golden necklace dripping with rubies the size of my eyeball. Much more satisfying. 

Where We Go From Here

How do you stock your dungeons? Do you do it all by feel, or keep it random? Are there other tables you use for stocking dungeons? I know that Papers & Pencils made their own table for stocking their Two Week Megadungeon. Are there any others our there that you know of? I'd love to hear about it. 


  1. I quite like this. I’ve also been looking back through your blog, and I think you’ve got some very good content. While I’ve been running stuff for a while, it hasn’t been D&D-ish rules/setting/genre wise — i.e. no dungeon crawls. Mostly SF and modern-ish (19th century+) with some 17th Century Flashing Blades. I decided to revisit my roots in early AD&D and traveller, and have that dungeons, ruins, rolling encounters and such to be rather strange to get back to. But interesting. And, while you expressed dislike of your earlier dungeon attempts, I quite liked it. Your content is helping me get back in touch with a different style of play than I’ve run for a while. So, thanks again for all this good content. I’ll probably be taking inspiration from a lot of it.

    1. Thank you so much! If you like the content on this blog, check out all the links on my blogroll sidebar. There's a lot of excellent content out there.

      I'm working on a pretty big dungeon right now (90 rooms) which I plan to blog about soon, so stay tuned.