Terraforming works

Atmosphere processors the size of cathedrals, breathing a dead world into a living one over a century. The machines need more care than the people, the weather is half made, and a fault in one stack can poison a continent.

Light
Lit
Going
Slow

Hear it

Hazards

  • Unbreathable air. There is air, but not air a human can live on: too thin, no oxygen, or the wrong gases. A mask and an oxygen supply are enough where the pressure holds; a full suit where it does not. D&D 5e: A creature holds its breath for 1 + its Constitution modifier minutes (at least 30 seconds), then gains 1 Exhaustion level at the end of each of its turns until it can breathe; it then loses all the Exhaustion it gained this way. Starfinder 2e: Thin atmosphere (GM Core): a few hours make a creature that is not acclimated fatigued; in severely thin air it attempts a Fortitude save every hour or becomes drained 1. With no oxygen at all, use holding breath and suffocating (Player Core). Armour environmental protections cover both. Archives of Nethys
  • Half-made weather. The processors pump heat and gas into a sky that does not yet know what to do with them: sudden fogs, acid drizzle, winds that spin up from nothing. D&D 5e: Heavy fog is Heavily Obscured: a creature trying to see something in it has the Blinded condition. Patchy fog is Lightly Obscured: Disadvantage on Wisdom (Perception) checks that rely on sight.
  • Processor fault. A stack fails and vents what it was cleaning: a cloud of hot, poisonous gas rolls down the valley. D&D 5e (House rule): House rule: a creature that starts its turn in the cloud without a sealed suit makes a DC 13 Constitution saving throw, taking 3d6 Poison damage and gaining the Poisoned condition until the end of its next turn on a failure, or half damage on a success. Starfinder 2e: Toxic atmosphere (GM Core): breathing it deals minor poison damage (1d6 to 2d6) every minute. Armour environmental protections do not stop inhaled poisons. Archives of Nethys

What may happen

  1. A processor stack's alarm goes off; the duty engineer is not at her post.
  2. It rains for the first time in this valley's history, and the workers stand out in it with their visors open.
  3. Shift change: a hundred tired people pass through the airlocks in silence.
  4. A valve has been closed by hand, deliberately, deep inside a restricted section.
  5. Seeding craft pass overhead, scattering lichen spores over the bare rock.
  6. The lichen seeded last year has spread, a faint green stain across a whole hillside. The workers come out to look at it.
  7. A cloud forms over the valley, white and small, the first that anyone here can remember.
  8. An ice hauler drops a cargo of comet ice into the crater lake, raising a cloud of steam and a cheer from the dam.
  9. An orbital mirror sweeps a bright spot of extra sunlight across the plain, warming the soil as it passes.
  10. A sensor at the top of a processor stack has failed, and the lift is out. The ladder is long.
  11. The company quota board shows the atmosphere two points behind plan, and every shift supervisor is in a foul mood.
  12. A small group of scientists holds up signs at the gate: they want this world left as it was found.
  13. Snow falls from a made cloud, thin and grey with dust, and melts in the processors’ warm wind.
  14. The seed vault holds frozen samples of every plant the works plan to grow. Its keeper lets nobody in without a form.
  15. An engineer who has worked here thirty years shows the party a photo of the valley when she arrived: bare rock and nothing else.
  16. A gas gauge reads differently from its neighbour. One of them is wrong, and the plan depends on which.
  17. A wall of dust rolls off the dry uplands, and the stack crews seal the intakes before it arrives.
  18. Tanks of engineered microbes bubble in the long shed, each one tagged with the gas it is meant to make.
  19. At night the stacks glow red at their tops, a row of beacons across the valley.
  20. The works canteen serves a stew made from the first crop grown in local soil. Nobody likes it, and everyone eats it.
  21. A worker takes off her mask outside for ten seconds, as a dare. She coughs, and grins, and says it is getting better.
  22. The board of the terraforming company arrives for an inspection. Every stack is polished, and the broken ones are hidden behind tarpaulins.
  23. A pipeline running from the polar ice has frozen solid at a pump house, and the reservoir is dropping.
  24. Imported bees are released in the greenhouse belt. The keeper watches the first one fly as if it were her child.
  25. The barometer at the works has crept up a little this year. The staff throw a party for a number on a dial.

Adventure hooks

  1. A processor is venting poison into a valley where a settlement was not supposed to be.
  2. The works' engineers are on strike, and the atmosphere they half-made is starting to slip.
  3. Something native was living in the dead world after all, and it is fighting back.
  4. A rival company wants one stack destroyed so the planet's new weather will favour its own lands.

Who and what is met

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

Other places among the stars

Orbital station, Derelict ship, Colony outpost, Precursor ruin, Asteroid field, Gas giant orbit, Deep space relay, Prison hulk, Research lab, Crashed freighter, Nebula, Neon city, Junktown, Spaceport, War front, Alien hive, Living ship, Undersea base, Lava foundry

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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