Some dungeons are old strongholds abandoned by the folk who built them. Others are natural caves or lairs carved out by monsters. Dungeons attract cults, groups of monsters, and reclusive creatures. Because of their varied origins and purposes, dungeons have a range of distinctive qualities. For example, a dungeon that serves as a stronghold for hobgoblin soldiers has a different mood and features than an ancient temple inhabited by yuan-ti.
You can use the Dungeon Quirks table to add distinctive character to a dungeon you’re creating or one in a published adventure. The quirks on the table reflect the characteristics of a dungeon’s creator, its intended purpose, its location, or some (often catastrophic) event in its history. You can use a single quirk or combine quirks as you see fit, and roll or choose a result that inspires you.
| 1d100 | Quirk |
|---|---|
|
01–02 |
Abandoned after internal strife devastated its population |
| 03–04 |
Abandoned because the site was cursed by a god or other powerful entity |
| 05–06 |
Abandoned by its original creators when a plague spread through the dungeon |
| 07–09 |
Amazingly well preserved ancient city inside a dome encased in volcanic ash, submerged underwater, or entombed in desert sands |
| 10–12 |
Built as a fortress guarding a mountain pass |
| 13–15 |
Built as a maze, either to protect treasure from intruders or as a gauntlet where prisoners were hunted by monsters |
| 16–18 |
Built as a stronghold but abandoned after it fell to invaders |
| 19–21 |
Built as a treasure vault to protect powerful magic items and great wealth |
| 22–23 |
Built atop a cloud |
| 24–26 |
Built beneath a city in catacombs or sewers |
| 27–29 |
Built beneath or on top of a mesa or several connected mesas |
| 30–32 |
Built by a religious group to serve as a temple and linked to the energy of other planes of existence |
| 33–35 |
Built by dwarves and decorated with enormous dwarven faces that have been defaced by its current inhabitants |
| 36–38 |
Built in a volcano |
| 39–40 |
Built in or among the branches of a tree |
| 41–43 |
Built to house a planar portal but abandoned when creatures or energy from the other side of the portal seeped into the dungeon |
| 44–46 |
Carved into a meteorite (before or after it fell to earth) |
| 47–49 |
Carved into a sheer cliff face |
| 50–52 |
Caverns carved by a beholder’s disintegration eye ray, with unnaturally smooth walls and vertical shafts connecting different levels |
| 53–55 |
Contains something that led to the downfall of its creators or inhabitants |
| 56–58 |
Dug as a burrow by a monster that might still live inside |
| 59–61 |
Entrance concealed behind a waterfall |
| 62–64 |
Floating on the sea |
| 65–66 |
Intended as a death trap to eliminate any creature that enters, perhaps to guard a treasure or to harvest souls for a necromantic rite |
| 67–69 |
Intended as a tomb |
| 70–72 |
Long known as the site of a great miracle or another auspicious event |
| 73–75 |
Made by amphibious creatures (such as kuo-toa or aboleths), using water to protect the innermost reaches from air-breathing intruders |
| 76–78 |
Made by a powerful spellcaster (perhaps a lich) as a site for magical research and experimentation |
| 79–81 |
Made by giants at a vast scale |
| 82–84 |
Natural caverns featuring a range of strikingly beautiful rock and crystal formations |
| 85–87 |
On an island in an underground sea |
| 88–90 |
On the back of a Gargantuan creature |
| 91–93 |
Originally constructed as a mine but abandoned when tunnels connected to dangerous Underdark tunnels |
| 94–96 |
Secreted away in a demiplane or in a pocket dimension |
| 97–98 |
Slowly abandoned as its creators died out or migrated away |
| 99–00 |
Transformed by multiple events or disasters over the course of centuries |
A dungeon built by giants offers enormous adventures.
A dungeon can range in size from a few chambers to a huge complex of rooms and passages extending hundreds of feet. The adventurers’ goal often lies as far from the dungeon entrance as possible, forcing characters to delve deeper underground or push farther into the heart of the complex.
A dungeon is usually mapped on a grid like graph paper, with each square on the paper representing an area of 5 feet by 5 feet. Appendix B shows several examples. If you play with miniatures on a grid, this scale makes it easy to transfer a map to a battle grid.
As you draw or adapt a dungeon map, keep the following in mind.
Asymmetry. Asymmetrical rooms and map layouts make a dungeon interesting and unpredictable.
Three-Dimensional Layout. Stairs, ramps, lifts, platforms, ledges, balconies, pits, and other changes of elevation make a dungeon interesting and make combat encounters in those areas challenging.
Multiple Pathways.Add multiple entrances and exits—to the dungeon as a whole and to individual rooms. By offering multiple paths the characters can follow, you present meaningful decision points to the players.
Wear and Tear. If you’d like to show wear and tear caused by time or the elements, collapsed passages can be commonplace, cutting off formerly connected sections of the dungeon from each other. Past earthquakes might have opened chasms within a dungeon, splitting rooms and corridors to make interesting obstacles.
Natural Features. Many dungeons include natural features. An underground stream might run through the middle of a stronghold, causing variation in the shapes and sizes of rooms and necessitating features such as bridges and drains.
Secrets. Add secret doors and secret rooms to reward players who take the time to search for them. For each door and room, consider their original purpose: were secret doors a defense against invaders, or do denizens of the dungeon scheme to keep secrets from each other? Secrets can help you develop the story of a dungeon.
Keep the following things in mind when designing a dungeon room:
Ceiling Support. Underground chambers are prone to collapse, so many rooms—particularly large ones—have arched ceilings or pillars to support the weight of the rock overhead.
Decoration. Most sapient creatures decorate their lairs. Statues, bas-reliefs, murals, and mosaics often adorn dungeon rooms. Equally common are scrawled messages, marks, and maps left behind by others who have passed through the area. Some of these marks are simply graffiti, while others may be useful to adventurers who examine them closely.
Exits. Creatures that can’t open doors can’t make a lair in a sealed room without some sort of external assistance. Strong creatures without the ability to open doors smash them down if necessary. Burrowing creatures might dig their own exits.
Common dungeon rooms fall into the broad categories described below.
Although it sometimes resembles a vault, a crypt can also be a series of individual rooms, each with its own sarcophagus, or a long hall with recesses on either side to hold coffins or bodies.
Crypt builders who are worried about undead rising from the grave lock and trap crypts from the outside—making the crypts easy to get into but difficult to exit. Other builders worried about tomb robbers make their crypts difficult to get into. Some builders make both entry and exit difficult, just to be safe.
Sapient, social denizens of the dungeon generally guard the entrances to their shared spaces. A guard post may just be a room with a table where bored sentries play a dice game, or it might be a pair of iron golems backed up by spellcasters hiding in balconies overhead.
When you design a guard post, decide how many guards are on duty, note their Passive Perception scores, and decide what they do when they notice intruders (see “Monster Behavior” in chapter 4). Some will rush headlong into a fight, while others will negotiate, sound an alarm, or flee to get help.
Most creatures have a lair where they can rest, eat, and store their treasure. Living quarters commonly include beds (if the creatures sleep), possessions (both valuable and mundane), and some sort of food preparation area (anything from a well-stocked kitchen to a firepit to a hunk of rotting meat).
Built dungeons often intersect with natural caverns, grottoes, and passages that are home to subterranean creatures, strange rock formations, pools of water, molds, fungi, and bioluminescent moss.
Any sapient creature might have some place dedicated to worship. Depending on the creature’s resources and piety, such a shrine can be humble or extensive. Adventurers are likely to encounter priests, cultists, and similar creatures there, and wounded monsters might flee to a shrine to seek healing.
A vault contains treasure and is usually sealed behind a locked or secret door. Many vaults are further protected by magic, monsters that can survive without food and water, and traps (see “Traps” in this chapter).
Sapient creatures often have laboratories, workshops, libraries, forges, and studios. Because such areas tend to contain valuable equipment, their doors are often locked and sometimes even warded by Glyph of Warding spells and similar effects.
The States of Ruin table can help you determine the general conditions of a dungeon area.
| 1d6 | Features |
|---|---|
| 1 |
Perilous. The area is dangerously worn and prone to collapse. Any impacts or damage to the structure, including from spells and other areas of effect, have a 50 percent chance of causing a collapse. |
| 2 |
Crumbling. Areas within the dungeon section are choked with rubble and have a 50 percent chance of being Difficult Terrain. Half Cover and hiding places are plentiful. |
| 3 |
Neglected. One dungeon hazard—such as brown mold, green slime, or yellow mold (see “Hazards” in this chapter)—is abundant. |
| 4 |
Abandoned. Most of the dungeon is deserted. Dexterity (Stealth) checks have Disadvantage because any sounds stand out as unusual. |
| 5 |
Secure. Ability checks made to break down doors, open locks, or carry out similar activities have Disadvantage. |
| 6 |
Thriving. The dungeon is heavily populated. Any loud noises draw the attention of nearby creatures. |