Jungle world

Jungle world
Morning fog over the rainforest at Taviu Hill, Ranau, in Sabah on Borneo · CEphoto, Uwe Aranas, CC BY-SA 3.0, Wikimedia Commons

A world of fiction: no known body is like it.

One forest wraps the planet from pole to pole: trunks taller than towers, a canopy so thick that the floor lives in green dusk at noon, and a wet heat that never lets up. No known world is like this one. Everything grows, climbs, strangles or eats something else, and a trail cut in the morning is closing by evening. Under it all lie the wrecks of ships that came before, and whatever learned to hunt their crews.

Light
Dim
Going
Hard

Hear it

Hazards

  • Wet heat. Hot, and so wet that sweat never dries: by midday the air passes 38 °C and a body can no longer cool itself. Suit chillers run flat out, water goes faster than planned, and the strongest walker slows by the hour. D&D 5e: At 38 °C (100 °F) or hotter, a creature exposed without drinkable water makes a Constitution saving throw at the end of each hour, DC 5 and 1 higher each hour after, or gains 1 Exhaustion level. Medium or Heavy armour gives Disadvantage on the save; Resistance or Immunity to Fire damage passes it automatically. Starfinder 2e: Temperature (GM Core): in high humidity the heat bands start 15 °F (about 8 °C) lower. From about 27 °C it is mild heat (fatigued after 4 hours of travel); from about 32 °C, severe heat (fatigued after 4 hours and minor fire damage, 1d6 to 2d6, every hour). Archives of Nethys
  • Lost under the canopy. No sky, no horizon, no landmark: under the canopy every direction looks the same, position fixes drop out, and the forest closes behind the party within a day. A wrong turn costs days. D&D 5e (House rule): House rule: each day without a working position fix or a marked trail, the navigator makes a DC 15 Wisdom (Survival) check. On a failure the party makes no progress that day; on a failure by 5 or more, nobody notices until the next day's check. Starfinder 2e: Getting lost (GM Core): failing checks to Navigate or Sense Direction can leave the party lost. Let the search run only a short while; if the party stays stuck, something comes to them: locals, predators, or a dangerous place. Archives of Nethys
  • Alien microbes. Life that never met a human: most of it cannot touch our chemistry at all, but nobody knows which of it can. Quarantine, filters and patience decide who goes home. D&D 5e (House rule): House rule: a creature that breathes the open air or eats unscanned food makes a DC 12 Constitution saving throw at the end of the day; on a failure it has the Poisoned condition for 1d4 days. A creature that succeeds three days in a row is safe from this world's microbes.
  • Food that is not food. The fruit looks ripe, the fish looks fat, and none of it may be made of anything a human body can use. Some of it is poison; most of it simply does not feed. D&D 5e (House rule): House rule: foraging finds no food a human can live on unless a lab or a DC 18 Intelligence (Nature) check proves it. Living on it otherwise is Malnutrition: a creature that eats less than half its daily food makes a DC 10 Constitution save at the end of the day or gains 1 Exhaustion level.
  • Pollen season. Something blooms and the air turns gold with spores. Most of the crew sneeze; one or two cannot breathe at all without a filter. D&D 5e (House rule): House rule: during the bloom, each creature without a filter mask makes a DC 11 Constitution saving throw each morning; on a failure it has the Poisoned condition until the next morning.

What may happen

  1. At noon the light under the canopy is still green and dim, and the air is so wet that a lens fogs the moment it is uncovered.
  2. Rain begins far above. Its roar on the leaves arrives a full minute before the first drop reaches the ground.
  3. The trail cut yesterday is gone, grown over by pale shoots as thick as a wrist.
  4. A long scar of snapped trunks runs down the slope, already furred with new growth, and ends at a hull half buried in roots.
  5. Inside the crashed hull a flight recorder still has power; its last entry is someone whispering, then nothing.
  6. For the third time today the whole forest falls silent around the party at once, and starts again a minute later.
  7. A cord of braided fibre is stretched across the path at ankle height, too neat to have grown there.
  8. A tree is hung with the helmets of earlier visitors, cleaned and polished, each one turned to face the path.
  9. At night the trunks light up in bands of pale blue that pulse slowly, brighter wherever someone has touched them.
  10. A brown river, warm as blood, blocks the way, and something long turns over under its surface.
  11. A cut vine weeps a sap that sets as hard as resin within a minute, gluing someone's glove to the blade.
  12. A troop of something long-armed and silent swings through the canopy overhead, hundreds strong, and is gone within a minute.
  13. A flower as wide as a table opens beside the trail and the air fills with a smell like warm bread; insects the size of hands converge on it.
  14. At the evening check, someone finds three soft grey discs stuck to their leg inside the suit, where a seam had opened.
  15. A pack lies in the middle of the trail, half open: rations, a knife, a photograph, and no owner.
  16. Roots have lifted a slab of worked stone out of the ground; its face is covered in fine grooves too regular to be natural.
  17. A call from the trees repeats a word someone in the party said an hour ago, in the same voice.
  18. A clearing opens where a giant has fallen; sunlight hits the floor for the first time in years, and the heat in it is like an open oven.
  19. A seed pod the size of a helmet drops from the canopy and bursts on the ground in a spray of white fibres.
  20. The crash site's emergency beacon has been switched off by hand: its cover is open and the switch thrown.
  21. Booted footprints in the mud circle the party's camp at fifty metres, then leave again.
  22. A column of red insects, each as long as a finger, flows across the trail and does not stop for an hour.
  23. Beyond the camp lights, eyes shine back from every level of the forest, near the ground and far up in the branches.
  24. A thick vine pours clear water when cut; the scanner calls it clean, apart from one compound it cannot name.
  25. Overnight a fine grey fuzz has grown on every fabric strap left outside the shelter.

Adventure hooks

  1. A rescue beacon calls from a crash site three days into the forest, and the survivors on the radio ask to be left alone.
  2. A trophy hunter hired a guide to bring back a canopy stalker's skull, and the guide has stopped answering.
  3. The company that holds the planet's charter wants proof that nothing intelligent lives here before the clearing starts.
  4. The wreck the party is sent to strip turns out to be a ship listed as arriving next month.

Who and what is met

Each is an SRD stat block under another name, as game masters reskin them.

Other worlds

Cold desert world, Ice moon with a hidden ocean, Methane world, Hothouse world, Volcanic world, Airless world, Ocean world, Tidally locked world, Earthlike world, Acid world, Swamp world

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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