Populating a dungeon

robus

Lowcountry Low Roller
So now that I’ve ventured into the interesting times of creating my own adventure, I’m now grappling with the fine art of dungeon population. Dyson Logos maps are saving me a ton of time when coming up with an interesting layout, but there’s still the task of figuring out what goes where.

So I was wondering how folks here approach this? Do you start with monsters and add traps and puzzles? What about adventuring day concerns?
 
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The first step is deciding on the intent of the dungeon. Maybe the PCs are just exploring for their own sake. Maybe the dungeon is the villain's lair. Maybe it's a deathtrap designed for foolish adventurers. Whatever the purpose, that's going to inform how you populate it.

The second step is to identify what encounters, set pieces or monsters you want or need to showcase. If it's the villain's Lair, obviously you need to put the villain and their henchmen in the dungeon. If there's a cool deathtrap you want to showcase, you have to make room for it.

Finally, you have to consider pacing. Where are the big important encounters? How much time and effort do the PCs need to go through to get there? Are you expecting to give them a chance to rest, or is there a Clock? That sort of thing.
 

MNblockhead

A Title Much Cooler Than Anything on the Old Site
I go both ways. Sometimes I start with the denizens and, assuming they or their forebears built the dungeon, I come up with the denizens and place appropriate traps and other features.

But often the denizen moved into and populated the dungeon long after the orginal builders created it. In that case, the dungeon may be designed as a Dwarven hold, but now has new inhabitants. Whether these new inhabitants have altered the dungeon but adding traps, new sections, etc. depends on the nature and abilities of the inhabitants.

I like for my dungeons to feel like there is some rational ecology to it. I'm not a fan of randomly populating rooms. I like to think about how they are feed themselves, dealing with waste, protecting themselves from various threats (including adventurers). That said, I try not to over think it.

There are some rare occasions that I use randomization. For example, I had a miles long network of kobold tunnnels in a mountain range. I had a large number of tunel tiles and I would shuffle them like cards and just lay them down as the party explored, rolling on tables for what various areas were used for, what they contained, and what could be encountered. But everything on that table fit into what could reasonably be found in a massive network of interconnected kobold warrens.
 

Celebrim

Legend
I start with the adventure. Then I decide what role the dungeon has in the adventure.

So for example, the adventure might be, "There is a plague going on in the city, and it's overwhelming the healing abilities of the local priesthood. A priest acquaintance of the PC's suggests it would really be helpful if they had some magical assistance in the form of a famous item that once belonged to the priesthood."

And the dungeon might be, "The item last was known to belong to an acetic hermit who built a rambling structure on top a remote tor which can be reached only by a long and steep staircase."

Having decided what the backstory might be, I then brainstorm what might be in the dungeon both in terms of the sort of rooms that might be in a hermitage, and what sort of things might have since come to occupy that structure and repurpose it. The later is done with an eye to a combination of believability (simulationist reasoning) and current PC level (gamist reasoning), as well things that might led to a variety of different types of game play or at least different tactical situations. As a further level of refinement, I might consider if I'm providing enough spotlight to all the party members, and try to avoid creating a lengthy scenario where one or more party members might feel they have little to do.

And since this is an adventure that revolves around 'finding the foozle', then both for gamist reasons (finding the foozle should be fun) and simulationist reasons (if the foozle hasn't been found before, it must be somewhat hard to find) I work out how the foozle is hidden and what clues might help lead the players to its hiding place.

Actually, maybe before a I type a whole lot more, let me just give you a link to build off first:

 

Zardnaar

Hero
I use a rough 1/3rd guide.

1/3rd of the dungeon will have an encounter
1/3rd will be something interesting. Trap, treasure, clued etc.
1/3rd empty. Might have have art or incidental treasure.
 

robus

Lowcountry Low Roller
The later is done with an eye to a combination of believability (simulationist reasoning) and current PC level (gamist reasoning), as well things that might led to a variety of different types of game play or at least different tactical situations.
That’s very much what I’ve been doing. The PCs are at level 19, so that’s making the gamist side interesting :)
 

Celebrim

Legend
That’s very much what I’ve been doing. The PCs are at level 19, so that’s making the gamist side interesting :)
Yeah. For anything over 15th level, which I confess is not a lot of experience for me, I would make increasing use of the planes to provide separation between normal reality with its great but still mundane challenges, and the sort of things that can actually challenge nigh unto demigod level PC's. This of course has the problem though of needing to up the ante in terms of the scale of your dungeons if you are to make them believable representatives of the iconic and archetypal.
 

robus

Lowcountry Low Roller
Yeah. For anything over 15th level, which I confess is not a lot of experience for me, I would make increasing use of the planes to provide separation between normal reality with its great but still mundane challenges, and the sort of things that can actually challenge nigh unto demigod level PC's. This of course has the problem though of needing to up the ante in terms of the scale of your dungeons if you are to make them believable representatives of the iconic and archetypal.
Funnily enough they’re already in a mage’s custom designed demi-plane so yep, things are definitely atypical. :)
 

Celebrim

Legend
Funnily enough they’re already in a mage’s custom designed demi-plane so yep, things are definitely atypical. :)
Demiplanes seem to be the solution Gygax hit upon, and so you are in good company. They have the advantages of one of the full planes with respect to providing challenges, but owing to their smaller and more intimate scale, they are much easier on the would be dungeon designer to map and populate.
 
So I was wondering how folks here approach this? Do you start with monsters and add traps and puzzles? What about adventuring day concerns?
When I created the Catacombs of the Lizard Kings (for my home Tomb of Annihilation campaign), I started with the theme & making the map. The theme was a dungeon used by lizardfolk priests of Semuanya to house the never-decaying corpses of Lizard Kings so that the "possessing demonic essence" could not leave them once the corpses decayed – thus, preventing the demonic spirits from going back to the Abyss, only to return in another Lizard King. So it was both a tomb and a containment site. I also knew I wanted it organized around a water feature, so some amphibious/aquatic monsters would be good, probably some undead. When figuring out the inhabitants, I created a big messy list of monsters that might fit, including:

Giant slug*, dracolisk*, skeletons or mummies (of lizardfolk), allip, shadow demon, ankhegs (jungle variety), pterafolk, quasit, guard drake, basilisk, giant subterranean lizard, giant crocodile, black abishai, hezrou, hydra, etc.

Then I compared some of my ideas to other parts of the adventure, and quickly realized that pterafolk & basilisks & giant crocodiles could feature elsewhere, and that a hydra was already present in another dungeon in TOA. I also added black pudding (as a place to dispose of innards from mummified corpses & a trap) and babau (vaguely reptilian looking) to the list as I worked. Be flexible. New monster ideas/connections will emerge as you work.

What I ended up with was this:

 

Paul Farquhar

Adventurer
I start with the story. Why does the dungeon exist? Why will the players be going in there? That gives a sense as to what kind of creatures populate the dungeon.

Same with traps and puzzles: why are they there? who made them? how do the dungeon denizens live with them?
 

Coroc

Explorer
I got one player who does require that dungeons make sense, e.g. a trap is there for a purpose to guard something, protect someone. Also the dungeon should not be overtly big with every room containing a bunch of mobs that never move around. (The later works only well if you got undead, outsiders or molds or other mobs who do not require food and drink as denizens).

Some of the best dungeons are made from structures which were something else in the past. Eg. a toppled tower, a sunken palace, attn. cliché :a former mine :). Dungeon walls can be made of plants in a jungle or walls of fire or force or it can be a pipe structure, maybe even filled with water.

If you design a city sewer dungeon for yourself, then try not to meet the trope of the vastly overdimensional sewer. If you got a medieval style city, even in the most dense building style most tenements will probably have no more than 3-5 stories.Eventually large areas are 1 to 2 story huts and houses. You will not have a cemented brickwalled walkable sewer for every subbranche of the canalization for such a city. Most housesare eventually connected with tubes where a rat fits in. Maybe along the main streets there are 2-3 walkable segments and maybe for the outlet into the river / sea there is some section where you can go by boat for a while but that is about it.

Population for the sewer should include rats, slimes molds maybe a few minor undead, maybe othyoughs or so. And then there is the secret entrance to the thieves guild / forbidden cultist shrine / uppermost level of the monster lair / underdark etc.
 

Paul Farquhar

Adventurer
When it comes to puzzles and traps, unless it's a tomb or vault they probably don't make much sense (goblins and kobolds like to set traps around their lairs, but they are usually pretty basic).

So use environmental hazards instead. e.g. scree slope with a risk of an avalanche can substitute for a bolder trap.

Use social puzzles - i.e. some of the denizens might be willing to talk.
 

Imaculata

Adventurer
I always start by thinking about a central theme and interesting encounters that I want to fit into the dungeon. I then design the lay out of the dungeon by thinking about what purpose each room serves. If the dungeon is home to intelligent creatures, then it should have rooms to fulfill their daily needs. Which means such rooms will probably have furniture in them, and maybe creatures going about their daily routine.

If the dungeon has traps, then there has to be a means for intelligent creatures to bypass the traps (unless the dungeon is uninhabited). Most of the time I will create an alternative path in the dungeon that bypasses the traps, or there will be a hidden lever/swith to deactivate the trap. I try to think about how these traps would function in any realistic sense. If the trap emits a jet of flame, then is this magical, fuel based or gas based? If any of the latter, surely there are reservoirs that can be refilled that are near where the trap is installed?

Another interesting thing to think about, is whether there are any unintended paths through the dungeon. Are there walls that have corroded with time? Do some of the intelligent monsters perhaps avoid parts of the dungeon that they have deemed unsafe? Have vermin borrowed through the walls, creating new tunnels? If so, maybe there are vermin opponents in some of the outskirts of the dungeon in addition to its normal population of bad guys. Can the players break down some of the walls with explosives and/or spells to create a shortcut? By giving some of the spaces their own story, this can inform where the monsters are, and where they are absent.

I also try to add obstacles in the dungeon that provide an exploration challenge, and require the use of certain skills. A weak floor may require careful movement, a collapsed stairway may require climbing, and a flooded passage may require swimming. Dungeons are often dilapidated structures, and parts of them may have broken down over time.

In my opinion it is just as important to add alternate paths in a dungeon, as it is to eliminate pointless filler space. I try to condense the dungeon in such a way that every space in it serves a function. If there is nothing to be done in any room/corridor, I either find something to put in it, or I eliminate it all together.
 
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Coroc

Explorer
@Imaculata Agree very muc hwith your post but one thing : an empty chamber from time to time is no problem, only if 90% of the dungeon is empty without a reasonable explanation then it gets critical.

Sometimes the almost empty dungeon is also a nice realistic approach. E.g. last session I did use a modded version of the dragon in "five shall be one" using a frost dragon. So there was no mobs, just things (some of the mcursed) explaining to the players that this was once a temple of hextor, until they got to the last room where they suddenly got assaulted by the dragon.

It is all about context. If it is a crypt robbed 10 times, then the only part of it not quite empty might be the 10% of it, hidden behind some secret door, which none of the robbers ever found.
 

Imaculata

Adventurer
@Imaculata Agree very much with your post but one thing : an empty chamber from time to time is no problem, only if 90% of the dungeon is empty without a reasonable explanation then it gets critical.

Sometimes the almost empty dungeon is also a nice realistic approach. E.g. last session I did use a modded version of the dragon in "five shall be one" using a frost dragon. So there was no mobs, just things
Ah, but then you have already put "things" in those rooms, and they are not truly empty, are they?

What I'm talking about is labyrinthine dungeons with dead ends with nothing in them, and lots of long twisting corridors, also with nothing in them. If the only choice that the players must make it whether they go left or right, then that is not a good use of your player's time. That is not to say that choosing to go left or right can't be interesting, but there must be something informing that choice.

For example, I am currently preparing a dungeon for an upcoming session. The very first room in the dungeon has walls covered in stone carvings (something the players can examine), and 3 doors, each with a distinct difference. One door is closed, but there is a faint magical humming coming from the other side. Another door is blocked by coral, and a third is slightly ajar. The players basically have to pick a door, but it is not a choice between 3 identical doors. They have something to inform their choice, and each door takes them to a different part of the dungeon where interesting stuff can be discovered.
 

Coroc

Explorer
What I'm talking about is labyrinthine dungeons with dead ends with nothing in them, and lots of long twisting corridors, also with nothing in them. If the only choice that the players must make it whether they go left or right, then that is not a good use of your player's time.
Yep that sort of dungeon is stupid. One of the many reasons why I always (have to!) mod official stuff, the maps also.
 

RhaezDaevan

Explorer
I recommend writing up a table with the types of "room encounters" you'd like the players to experience. Roll against the table to fill out the rooms, then can review what you have and adjust from there. I find it easier than starting from scratch.

Example
1 - Nothing
2 - Trap
3 - Monster
4 - Treasure
5 - Trap + Treasure
6 - Trap + Monster
7 - Monster + Treasure
8 - Monster + Trap + Treasure

Then could have tabes for which trap or monster or treasure are encountered.
 

aco175

Explorer
I generally have a theme before I make the dungeon. Right now I'm making a gang hideout and Know that I'm using a lot of thugs and bandits. I have a few other humanoids with a mage and higher level fighter type. It gets boring fighting the same monster all the dungeon, so I will throw in some 'pets' like a drake or owlbear that is captured. I also like to throw in something not expected like a place to hide and take a short rest.

If I make the map first, I like to add elements of the maker to the feel of the place. Maybe a giant statue of a dwarf in an old dwarf mine not overrun by zombies.
 

Imaculata

Adventurer
I generally have a theme before I make the dungeon. Right now I'm making a gang hideout and Know that I'm using a lot of thugs and bandits. I have a few other humanoids with a mage and higher level fighter type. It gets boring fighting the same monster all the dungeon, so I will throw in some 'pets' like a drake or owlbear that is captured. I also like to throw in something not expected like a place to hide and take a short rest.
You highlight something very important here. Monster diversity is a good idea, but a lot of diversity in the encounters can also be created by just adding different variants of the same enemy. If for example the dungeon is a bandit's hideout, then you could have bandits with swords, but also with crossbows, in heavy armor, and a mage. Plus the bandits could have a pet, which could be any kind of nasty beast.

Encounters become much more interesting if there is a priority target. For example, you could have a mage in a library, guarded by two armored thugs. The mage could be a serious threat to the players, so the players may try to target him first. But of course because he is important, the bandits may stay in a tight formation around him. Perhaps they were instructed to do so by their leader.

Whenever there is a priority target, the DM would do well to put this enemy in an area that is harder to reach. You can place bandits with crossbows on a balcony, overlooking a large room. And if the bandits have a crocodile pet (for example), the dungeon may also feature some aquatic terrain where the croc has a distinct advantage. Another thing I like to do, is to add additional objectives to any encounter. Any straight forward battle is made way more interesting if the enemies can ring an alarm bell to call reinforcements. So the players will have to intercept a guard running for the bell.
 

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