Abyssal

Chaos and hunger without a bottom: pit after pit, each one worse than the last, ruled by whichever fiend is strongest this week. Nothing keeps its shape for long, not the land, not the paths, and not the visitor’s temper. One falls in through a torn portal or is dragged in; leaving takes a spell, or a long climb toward an exit that keeps moving. Every creature there wants something, and none of them wants to share.

Light
Dim
Going
Hard

Hear it

Hazards

  • Creeping cruelty. The place feeds the worst in everyone. Kind words get harder to say each day. D&D 5e (House rule): Each day here, each creature makes a DC 12 Wisdom save. On a failure, the GM gives it a cruel or selfish urge it must act on once before the next long rest, or take 1d6 Psychic damage when it refuses.
  • A glimpse below. Sometimes the ground opens on the layers below, and what lives there looks up. D&D 5e: Whoever sees it makes a DC 20 Wisdom save or is Frightened, repeating the save at the end of each of its turns.
  • Fiendish idols. Crude idols stand at every crossing. Touching one is like having the mind clawed. D&D 5e: Whoever touches one makes a DC 15 Wisdom save, taking 3d6 Psychic damage on a failure, or half as much on a success.
  • Opening pits. The ground splits without warning onto the next layer down. D&D 5e: A fall deals 1d6 Bludgeoning damage per 3 m (10 feet), up to 20d6, and leaves the faller Prone unless it took no damage. Landing in water or another liquid: a DC 15 Strength (Athletics) or Dexterity (Acrobatics) check as a Reaction halves the damage.

Adventure hooks

  1. A messenger of the gods hangs in chains in a demon warlord’s camp. Freeing it will bring the whole horde down on the party; leaving it means the gods will hear who walked past.
  2. A deserter from a demon horde offers to guide the party to an exit, if they help him take revenge on his old master first. His idea of revenge is long and detailed.
  3. Two demons are fighting over a mortal’s soul, and the mortal is still very much alive and would like them to make up their minds. He hires the party to arbitrate.
  4. The way out of the pit moves every hour, and the party has a map that shows where it will open next. The map was drawn by a demon, who is following them to see if it works.

What may happen

  1. Two packs of fiends tear into each other over a scrap of meat. Neither has noticed the party yet.
  2. The sky turns the colour of a fresh bruise and starts to rain something warm.
  3. A sweet voice offers one of the party exactly what they want most, just around the next corner.
  4. The party sees a shining exit on the cliff above. By the time they reach the spot, it is three ledges higher.
  5. A winged being of light, chained and dimmed, is displayed as a trophy in a fiend camp.
  6. The ground is warm and soft, and slowly breathes.
  7. A small, scared fiend offers to sell its master’s secrets for safe passage.
  8. A cloud of flies the size of thumbs rises from a carcass and comes buzzing.
  9. Banners of skin mark the border of a warlord’s territory. Beyond them, the screams stop.
  10. The party meets itself coming the other way: same faces, wrong smiles.
  11. A river of something red and thick blocks the way, with bones for stepping stones.

Creatures

To bring back

Howler Fang, Nabassu Wing, Vargouille Tongue, Bodak Eye, Succubus/Incubus Blood, Wastrilith Acid Venom, Balor Heart, Sibriex Bile

Other planes

Feywild, Shadowfell, Ethereal, Astral, Elemental Fire, Elemental Water, Elemental Earth, Elemental Air, Infernal, Celestial, Hades

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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