Creating and Stocking Dungeons

INTRODUCTION

I will again make this disclaimer: I use the following method not because the official AD&D method (or other) are bad, but just because they work better for my workflow. I stole from AD&D and tons of other sources in coming up with it.

For my method, you can use two different paths: either you pick an already existing dungeon (I suggest this excellent generator as a basis that you can edit and modify to pimp it up) and fill it, or you just go with the flow and use some of my generators to determine what kind of room it is. For the latter, I sometime go with dungeon cards that exist or whatever other method you prefer and have.

If you create a megadungeon, you just have to follow the same method, except that you design every level by considering the others. It's especially important for monster allocation and paths. For this, I suggest reading articles on the Three Clue Rule and on Jacquaying dungeons.

There's also good guides for dungeon stocking here, or tables here. In addition to that there's general question you'll want to ask yourself about the dungeon like who made it and who is using it now. Some of this kinda stuff is covered here.

A mandatory read for any dungeon is Philotomy's Musings.

DUNGEON GENERATION WORKFLOW

Dungeon Location and Meta (modified from 5th DMG)

Location determines where the dungeon is situated. This can help you flesh out the hex where it is and so on.

Roll	Location d12
1	Building in a city
2	Catacombs or sewer beneath a city
3	Beneath a graveyard
4	Beneath a ruined castle/temple
5	In a chasm
6	In a cliff face
7	In the open
8	Beneath or on top of a mesa
9	On a mountain peak/promontory
10	Underwater
11	On an island
12	Exotic

For Exotic location:

	Exotic
1	Around a geyser
2	Behind a waterfall
3	Buried in a avalanche/sandstorm/landfall
4	Sunken in a swamp
5	sealed inside a magical dome of force
6	Pocket dimension (hidden portal or protected portal)
7	Devasted by a magical catastrophe
8	Ship (underwater, on water, outside of water)

Type determines the kind of dungeon it is. This will help you flesh out the description that you give and how you implement the different room functions with relations to the usage of the players of the facilities and so on. It will also help you set out what kind of traps and such.

	Type d4
1	Ruins (abandonned by original creator)
2	Caverns (natural or underworld)
3	Occupied (actively used)
4	Vault (sealed for something, or sealing something)

Purpose determines the present purpose of the dungeon. With this and the next point (Monster), you should already have a pretty clear idea of the "story" of the dungeon. Because yes, the dungeon is kind of a character in itself that will try to fight out the players.

	Purpose d8
1	Home/Settlement
2	Fortress/Castle/HQ
3	Temple
4	Prison
5	Library/Research
6	Crypt/Tomb
7	Factory/Utility
8	Other

For temples, I created my own table that suits my setting, so you'll have to adapt it:

	Temple cult d8
1	Demon
2	Demon
3	Demon
4	Arta
5	Tizan
6	Frumos
7	Elemental
8	Natural gods (dragons)

And then one last thing to tie everything together, the actual history of it plus the layer of the dungeon (i.e. each layer represents a previous use and disuse; therefore a fourth layer dungeon is old as life itself, whereas a first layer means it's the first inhabitants or almost). This should help you choose the monsters. 

	History d20
1-3	Abandonned by creator
4	Abandonned due to plague
5-8	Conquered by invaders
9-10	Creators destroyed by attacking raiders
11	Creators destroyed by discovery made within the site
12	Creators destroyed internally
13	Creators destroyed by magical catastrophe
14-15	Creators destroyed by natural disaster
16	Location cursed (by gods or demons)
17-18	Original still in control (or their creation/guardian)
19	Overrun by planar creatures
20	Other

	Layer d4
1	First
2	Second
3	Third
4	Fourth

Monster Allocation

Here you will choose the monsters for the dungeon, or the dungeon level if you have a megadungeon. I like having one theme of monsters for the overall dungeon, and one theme of monster for every level. It doesn't mean that there is only one type of monster itself: a theme can be comprised of multiple type of monsters.

For example, one of my megadungeon is ruled by a vicious Minotaur that discovered a powerful artifact. He slew his companions and decided to take over a huge tribe of Troglodyte to conquer a dungeon that was mostly occupied by giant insects (centipede and ankhegs). He barricaded the lower levels, because they contain powerful undeads that are ancient protectors of the dragon that sleep beneath. So you have one main theme: Dragon dungeon conquered by troglodyte. So you have troglodyte pretty much every level. But the first levels and the outset of it (caverns, etc.) are also full of insects (that fights with troglodyte). The lower levels, beneath the Minotaur, is full of powerful undeads. The last level has a dragon.

To do this, I suggest two methods: create a general concept and just go with the flow, or roll one random powerful monster (make your own list according to your setting) for the overarching theme, and then roll 2-3 TYPES monsters for every level, and adjust the HD according to the depth of the level. If you roll undead on level one, it will be skeles and zombies, whereas if you roll it on level 8, it might be wights and vampires.

I personally created a huge lists divided by types of HD with types of creatures, but sharing it would be useless as I use personal monsters and so on. Categories look like: corporeal undead, mummufied corpse, uncorporeal undead, skeletal undead, felid, giant birds, horses, monstrosity, humanoid monstrosity, mythological creatures (greek etc.), giants, animals, feywild, lizard-type, air elemental, water elemental, fire elemental, earth elemental, construct, slime, plant monsters, aberations, eye (gas spore, gazer, gauth, etc.), fish, giant insect, spider, snake, worm, ape, boar (including catoblepas), humanoids, demons, shapechanger, kuo-tua, machines, fiends and outsiders, dinosaurs, psionics, etc.

Then you can just adjust the HD according to the level and voila.

Overall Design

At that point, you should decide how many levels you want, and they connect between each other. This is where the Jacquay thing will come in handy. Here are some principles and tips for it:

• Multiple entrances. 
• Loops (having branches that gets back together to avoid dead-ends).
• Multiple level connections. 
• Discontinuous level connection (level one going to level three, then two, then five, back to three, etc.). 
• Secret/unusual path (ex: caved-in tunnel, teleportation that must be decoded, submerged bypass, etc.). 
• Sub-level (depart from main dungeon). 
• Divided levels (where you can go down to a particular level at two different places, but they don't connect, effectively creating two different "level"). 
• Nested Dungeons (two separate dungeons that gets back together further down). 
• Minor elevation shifts. 
• Midpoint entry (ex: in a tower, players can decide to get in at different level, not necessarily level one).

Some "design philosophy" points:

• Size (doesn't need to be big). 
• Beware the sprawl (no need for infinite branching). 
• Structure in the dungeon (some areas are easy, others difficult; some are easy to access, others not; some will transfer far to near and near to far, etc.). 
• Having landmarks.

You can use various Level Design Tools to achieve all of the above:

• Stairs. 
• Slopes. 
• Chutes. 
• Ladders. 
• Trapdoors. 
• Windows. 
• Teleports. 
• Traps. 
• Multi-level chambers. 
• Basket and pulley. 
• Ethereal travel. 
• Rivers. 
• Underwater. 
• Collapsed passage. 
• Transport. 
• Being swallowed. 
• Brute force. 
• Combo platter (ex: ladder that brings underwater, elevator that gets out, etc.). 
• One connector, multiple level. 
• Invisible transitions. 
• False stairs. 
• Misleading stairs. 
• One-way paths. 
• Remote activation. 
• Banana Shape level (foreshadowing; for this, play E1M1 of Doom 1 to get a feeling). 
• Overlooked secrets (ex: when you take a path that leads back from behind a statue, hinting that other such statue in the dungeon might be actual hidden paths).
• Raised bridge. 
• Lava and acid. 
• Illusory walls.

Optional: 5 Room Dungeon

To help with the "design philosophy points", you can use a variation of the 5 Room Dungeons. The idea behind the 5 Room Dungeon is mostly useful for small thematic dungeons, as they are very linear in their overall concept. That being said, it's possible to integrate some of its aspect into any big dungeon.

What you do is that you think of it as a checklist (of sort) to organize both the overall dungeon and each level of your dungeon. To give an example, I will share what I did (without details) for my Minotaur dungeon:

• Overarching 5RD:
• Entrance with guardian: First level is full of traps and indications that troglodytes are ruling and don't want anybody here
• Roleplaying challenge/puzzle: There is multiple paths going down, players have to find the right "level" that keep going into the depths
• Tricks or setback: The "final boss" is the Minotaur, but he's not anything final. He actually barricaded the way going down because he was afraid of it !
• Big Climax: Fight with the guardians of the Dragon to learn that...
• Revelation: There is a dragon. He's not hostile, he's sleeping. He's full of loot also. 
• 1st level: 
• Entrance with guardian: There is an ambush with walls with holes where they can shoot their makeshift crossbow and poke with spears.
• Puzzle or roleplaying challenge: They meet a captured humanoid in a prison cell. 
• Trick or setback: Some areas are closed off and there is a lot of passage blocked with giant insects. 
• Subtrick: There are teleporters within the level, but they have so few charges left that every use has a chance of shutting them down, trapping a party member somewhere else alone.
• Climax: A room full of goons that guards one of the way down.
• Revelation: There is two way down. 

Some of those are not very complicated, but as you "check in the box", it makes you think of your level design and it makes sense for players to go through it. Can they go around some of the points or do them in disorder ? Sure, and it doesn't matter. At that point, agency is in their hand and you just go with the flow. 

Here is my checklist that I use to give me ideas with the 5RD for real dungeons. I roll 1d6 for each of the five "rooms":

Room	1	2	3	4	5	6
Entrance with Guardian	Trap	Multiple entrance but most leads to dead-end	Entrance needs a key/password	Neutral Guardian	Aggressive Guardian (ambush)	Entry without visible exit (ex: hole)
Puzzle or Roleplaying Challenge	Intricate trap	Puzzle	Challenge with multiple solutions	Coded Door (ex: pacifist chest)	Permanent NPC (ex: Ghost, Golem, etc.)	Impermanent NPC (ex: adventurer, ennemy)
Trick or Setback	Challenge (start from beginning)	Teleport, trap, map change, illusion etc. that cuts the party	They find a door/chest, but the key is not here	Challenge that tricks them	Rescue NPC that may be dangerous/booby-trapped, etc.	Shortest way seems blocked, needs to do a long detour or find a way to go through
Big Climax	Environmental boss	Multiple bosses	Only the boss has information about something important (exit, lower level, etc.)	Item boss (he uses something to gain advantage)	Boss has something he threathen to destroy	Cues to destroy the boss all over the dungeon
Reward and Revelation	Hints at a bigger boss/donjon/item elsewhere	Le boss ressucite en partie ou en totalité	Memorable Lore drop	Bonus treasure that leads elsewhere (teleport, tunnel, etc.)	Misunderstanding (PCs and monsters could have been allies)	Neutral guardian that protects a treasure

Room Function

Now you know the story of your dungeon, you have your level laid out and you know what kind of monsters will be in. You can start putting stuff in the rooms. If you picked a random dungeon, or already have a vague idea of the bigger story of the dungeons, you can skip right to here everytime and just go with the flow.

This is a modified Gygaxian room filling roll using a d20:

	Event d20
1	Nothing
2	Nothing
3	Nothing
4	Nothing
5	Nothing
6	Nothing
7	Nothing
8	Nothing
9	Keyed Door
10	Trapped Treasure
11	False Treasure
12	Guarded Treasure (roll monster)
13	Unguarded Treasure
14	Unguarded Treasure
15	Trapped Door
16	Trigger Trap
17	Tricks
18	Monster (omen)
19	Monster (omen 1st)
20	Monster

Room Description
What comes next is just bunch of tables that will help you flesh out the rooms.

Corridors

d8	Corridor
1	Dead End
2	Small Space
3	Hole bottom
4	Barricade
5	Contains...
6	Contains...
7	Danger
8	Magical

Room type (d8) + the subtype (d6)

Room Type
1	Public Assembly
2	Containment and Imprisonment
3	Pleasure/Relaxation
4	General Function
5	War and Conflict
6	Deities and Worship
7	Learning and Knowledge
8	Special Utility

d6	Public Assembly	d6	Containment	d6	Pleasure/Relaxation	d6	General Function	d6	War and Conflict	d6	Deities and worship	d6	Learning	d6	Special
1	Throne room	1	Bestiary/kernel	1	Arena	1	Bathroom	1	Armory	1	Chapel	1	Classroom	1	Kitchen
2	Antechamber	2	Cage	2	Banquet	2	Bedroom	2	Barrack	2	Crypt	2	Divination chamber	2	Forge
3	Amphitheather	3	Cell	3	Gallery	3	Dormitory	3	Guardroom	3	Embalming Chamber	3	Laboratory	3	Office
4	Audience hall	4	Oubliette	4	Maze	4	Reception	4	Gymnasium	4	Meditation chamber	4	Library	4	Garage
5	Courtroom	5	Prison	5	Museum	5	Foyer	5	Interrogation	5	Shrine	5	Observatory	5	Workshop
6	Great Hall	6	Stockade	6	Pool	6	Salon	6	Training	6	Temple	6	Study	6	Service room

Description : d6 + d12 + d10 + d20 + d8
d6	Size	d12	Shape	d8	Smell and air	d10	Danger	d20	Contains	d8	Magical
1	Small (15 x 15)	1	Collapsed, not all accessible	1	Clear and earthy	1	Yellow Mold/slime	1	altar, statue, etc.	1	magical automation (unseen servant, etc.)
2	Medium (30 x 30)	2	Circle	2	Foggy and salty	2	Fire/cold	2	arch, pillars, etc. (can hide view)	2	protection (protective shield on a door, corridor, chest, etc.)
3	Medium	3 - 6	Rectangle	3	Smoky	3	Activated repeating trap	3	oil, inflammable, etc.	3	physical effect (fire door, items floating, no gravity)
4	Medium	7 - 10	Square	4	Hazy and dank, moldy	4	Huge gap/hole	4	ropes, ladder, etc.	4	visual effect (no shadows, etc.)
5	Large (60 x 60)	11	Pentagon/hexagon	5	Stale, obscured	5	Cave-in	5	fireplace, forge, etc.	5	visual illusion (illusory door/angles, etc.)
6	Hall (90 x 90)	12	T	6	Dusty and dry	6	Trick	6	decoration (fresco, mosaic, etc.)	6	auditory illusion (sounds, music, etc.)
				7	Chlorine and difficult to breath	7	Bridge	7	food, waste, latrine, etc.	7	magical utility (magical lights, etc.)
				8	Putrid and damp	8	Vermin/fungi	8	plants/fungi, animals, etc.	8	antimagic field (general, or specific like anti-divination, etc.)
						9	Toxicity that needs to be purified	9	instruments, tools, etc.
						10	Flooding	10	bath, pool, etc.
								11	water (fountain, etc.)
								12	holes in wall/floor
								13	stuck/inaccessible door/trap
								14	barricade
								15	used trap
								16	scratch on walls etc.
								17	furniture with equipements on/in
								18	writings
								19	strange substance
								20	magical

Subtables (Oddities, Traps, Tricks, Challenges and Puzzles, Restocking)

I already wrote about traps, tricks and restocking dungeons. I will therefore only speaks of oddities and challenges.

Oddities

Oddities are things you can put in your empty room when you think they are too stale, or instead of doing a long list of rolls to describe a room, you want something quick that will stick out. It's advisable not to put too much into your rooms: as I said before, emptiness has its own role in a dungeon.

	Oddities Door	Oddities wall
1	Every third time used, it casts a spell on any who pass	surface act like water
2	Door gives visions	unstable surface
3	Door is electrified	covered (vegetation, skin, etc.)
4	Door is intelligent and aligned	trampoline
5	Door is an illusion	molten
6	Contact with door causes it to cast spell	absorbs sound
7	Door is rotten	rebound spell
8	Door is invisible	strange material (metal, block of ice, etc.)
9	Door is magnetized	strange mosaic
10	Door is hot	caltrops (invisible)
11	Door vanishes when closed	electrified
12	Door fakes noises for listeners	quicksand
13	Door locked, destroys weapons used to break it down (as rust monster)	phosphorescent
14	Door is a mirror	blinding
15	Door repels metal	glows
16	Door is fire/acid/water etc. proof	extinguishes torches
17	Door is sticky	anti-magic
18	Door is curtain of darkness	spike, blade
19	Web/net	uneven
20	Strange writings	carved

You could also have a list of "random events" or "unique events" like:

• A much-worn digging tool made of a sharpened human femur. In a pinch it would also serve as a light club or short sword.
•  An iron maiden, a terrible torture device that the gaolers call Lucinda, supposedly after the spirit of the one who haunts the device.
• Leering skulls embedded in the wall
• Bubbling vats of thick liquid
• Burning violet braziers
• etc.

Challenges

Challenges are anything that can stop PCs in their tracks, but provide for a fun problem-solving portion. It can be anything, and it doesn't have to be very big. Here is a list of examples:

• Invisible bridge
• Appearing bridge
• Object high out of reach (can only see a reflection, in a narrow hole, etc.)
• Bottomless hole
• Treasure inside a monster
• A treasure that stops a trap from springing
• Doppleganger
• Demon trapped in a circle of protection with a magical object
• Mislabeled potions
• Vines for swinging above a pit that are monsters limb (a classic would be ropers)
• Illusionary/fake treasure that is a creature (or straight-up mimic)
• Maze with invisible walls
• Tesseract rooms
• An altar that diminish 1/6 any object or creature that goes on it
• A trap that targets your companions
• Illusionary fire wall
• etc.

CONCLUSION

When you have a good idea, you don't need to roll. Those rolls are made to make you think and find new ideas to fill in. The only thing I'd probably always roll is the room content (d20 Gygax method) to make sure I have a good proportion of each thing. 

Feel free to share more content in the comments.