Dungeon

Stone corridors and rooms dug or built under the ground, long after their makers left or died. There is no light but what the party carries, the air is still and every sound carries far. People come for what was hidden or locked away here, and fear the traps left to guard it and whatever has moved in since.

Light
Dark
Going
Slow

Hear it

Hazards

  • Darkness. Beyond the torch, nothing. Whatever waits in the dark sees the light coming long before the party sees it. D&D 5e: An unlit room is Heavily Obscured: a creature trying to see into it has the Blinded condition. A torch or lantern gives Bright Light around it and Dim Light further out, where Wisdom (Perception) checks that rely on sight have Disadvantage. Darkvision turns Darkness into Dim Light within its range, in shades of grey.
  • Hidden pit. A slab of floor like any other swings down under the first foot, and someone drops into a hole with smooth walls. D&D 5e: A 3 m (10 ft) pit hides under a hinged lid that looks like the floor. A creature that steps on it falls in and takes 1d6 Bludgeoning damage; the lid stays open. A Study action and a DC 15 Intelligence (Investigation) check spot it, and an iron spike wedged in the gap keeps it shut. Getting out needs a Climb Speed, climbing gear or magic. Deeper pits for stronger parties: 9 m and 3d6 (levels 5 to 10), 18 m and 6d6 (11 to 16), 36 m and 12d6 (17 to 20).
  • Poisoned darts. A click underfoot, then a hiss from the walls: little holes behind the cobwebs spit darts. D&D 5e: A pressure plate fires darts from hidden holes. Each creature in their path makes a DC 13 Dexterity save or is hit by 1d3 darts, 1d6 Poison damage each. It resets at the start of the next turn, up to three times. A Search action and a DC 15 Wisdom (Perception) check find the holes (plug them with wax or cloth) or the plate (wedge it with an iron spike). Stronger: 2d6 per dart (levels 5 to 10), 4d6 (11 to 16), 7d6 (17 to 20).
  • Falling net. A wire across the passage, a rush of air, and a weighted net comes down on whoever leads. D&D 5e: A trip wire drops a 3 m (10 ft) square net on the first creature to cross it: DC 10 Dexterity save or it has the Restrained condition (Huge or bigger escapes automatically). An action and a DC 10 Strength (Athletics) check frees it or someone within reach. A Search action and a DC 11 Wisdom (Perception) check spot the wire, which is then easy to cut or step over. Heavier nets raise both DCs to 12, 14 or 16 for levels 5 to 10, 11 to 16 and 17 to 20.
  • Rolling stone. A rumble from above, and a ball of stone as tall as a man comes down the corridor. There is nowhere to stand aside. D&D 5e: For strong parties (deadly at levels 11 to 16). A hidden plate releases a stone ball 3 m (10 ft) across that rolls Initiative with +8 and moves 18 m (60 ft) a turn in a straight line until it hits a wall. A creature whose space it enters makes a DC 15 Dexterity save or takes 10d10 Bludgeoning damage and falls Prone. A Study action and a DC 15 Intelligence (Investigation) check work out the plate; an iron spike under it stops the trap. As an action, a DC 20 Strength (Athletics) check slows the stone by 4.5 m (15 ft) a turn. The stone has AC 17, 100 Hit Points and a Damage Threshold of 10.

Adventure hooks

  1. A rival band went into the old vaults a week ago, and only their dog came out. Their patron wants the map they carried, and is noticeably less interested in them.
  2. An old locksmith says he made every lock down there for the builder, forty years ago, and kept a copy of each key. He will lend the ring for half of whatever the keys open, and he is coming along to count.
  3. A family of goblins has set up a toll at the only stair, with a written price list. They are polite, they give receipts, and their prices went up when they saw the party’s boots.
  4. Behind a locked door, a prisoner begs to be let out. He knows things about the place that nobody could know, including the party’s names and which of them will die in here.

What may happen

  1. A cold draught comes from a blank wall. Somewhere behind it, there is a room.
  2. Chalk arrows on the wall, drawn by someone who came before. The last one points back the way they came.
  3. An open pit with an old skeleton at the bottom, still holding a coin purse and a lantern.
  4. Water drips somewhere ahead, steady as a clock. It stops when the party stops.
  5. An iron-bound door, locked, with fresh scratches around the keyhole.
  6. A voice from behind a grate begs to be let out. It swears it is a lost traveller.
  7. The cold remains of a camp: a fire ring, torn bedrolls, a page from a diary.
  8. The torch flame leans and gutters toward a side passage, as if the dark were drinking the air.
  9. Lights ahead: another band of adventurers, tired and wounded, who want the same treasure.
  10. A stone door with a face carved in it. Its mouth asks a riddle and waits.
  11. Fresh bones, gnawed and cracked for the marrow. Something big eats here.
  12. A name echoes down the corridor. It is the name of one of the party.
  13. A scrap of map under a stone, showing three rooms the party has not found yet.

Creatures

To bring back

Brutacian Lung, Bugbear Tooth, Fire Beetle Glands, Ghoul Bile, Ooze Portion, Rat Heart, Troglodyte Thumb Nail, Worg Tongue, Zombie Ichor, Cockatrice Liver, Crawling Claw Nail, Devil Tooth, Doppelganger Brain, Echo in Stone, Gargoyle Fang, Ghost Light, Ghoul Tongue, Giant Spider Perfect Eye, Gnoll Fang, Hag Index Finger, Imp Leg, Kenku Beak, Mimic Slime, Nothic Iris, Phase Beast Heart, Spectator Eye, Ankheg Antennae, Basilisk Throat, Cranium Rat Brain, Death Hound Skin, Deathlock Heart, Ectoplasm Portion, Grell Beak, Hag Brain, Lamia Nose, Meenlock Claw, Minotaur Heart, Nabassu Wing, Neogi Venom Sac, Phase Spider Egg, Scarecrow Spark, Vampiric Dust, Vargouille Tongue, Beholder Eye, Bodak Eye, Catoblepas Eye Gland, Golem Life Spark, Hag Moldy Heart, Mummy Soul, Naga Perfect Scale, Oblex Slime, Revenant Soul, Roper Bile, Shadow Veils, Skullfire Essence, Alhoon Brain, Balor Heart, Banshee Dust, Death Knight Ashes, Lich Dust, Medusa Heart, Mummy Lord Heart Dust, Elder Oblex Slime, Rakshasa Palm, Shadow Dragon Gland, Silence of the Void, Vampire Dust

Other sites

Crypt, Graveyard, Ruin, Sewer, Fortress, Mine Works, Temple, Laboratory, City

This work includes material from the System Reference Document 5.2.1 ("SRD 5.2.1") by Wizards of the Coast LLC, available at https://www.dndbeyond.com/srd. The SRD 5.2.1 is licensed under the Creative Commons Attribution 4.0 International License, available at https://creativecommons.org/licenses/by/4.0/legalcode.

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