OSR: Archaeans

Archeans are a race from Patrick Stuart's Veins of the Earth. Check out pp. 26-28 if you want to learn more. Trench Heralds from Fire on the Velvet Horizon also resemble Archaeans. Perhaps they are Archaeans in another form, or a thing they created. Anyway, they overlap.

(Also, I'm spelling my version with an extra "a"; archean is an era, archaean is a domain.)

Chenthooran Nambiarooran
Major Features
-plasma-glass archaebacterian people
-slow-moving, aloof
-impossible chemosynthetic biology
-astronomers, scholars, explorers, but from a very different perspective
-not intentionally deadly but accidentally deadly

Encountering an Archaean
Usually,  you run into them. An Archaean in a dead sprint moves as fast as a waltzing dancer. Their usual walking pace is glacial.

Up ahead, in a cave, you see a faint blue-green glow and a steady hiss. A living glass sculpture is examining a layer of stone, brushing the surface with knife-edge fingers, spreading faint clouds of grey fumes into the air. It will probably ignore you unless you try to get its attention.
Chenthooran Nambiarooran
How to Attract Attention
Noise works. The Archaeans can sense and decode vibrations in the air. If it has heard your language before, it will try to communicate. If it hasn't, you might need spend a few days speaking to it in call-and-response repetition or try a few different languages. They speak all elemental languages, and the chemical languages of oozes and myconids.

If you want one to follow you (or move to a different area) it needs some way to detect you. A trail of rust flakes is a foolproof method. The Archaeans see metal more easily than flesh. Seasoned explorers and diplomats carry unique pendants made from lead and crystal or strange iron-attracting lodestones.

Like someone speaking through a fan. Choppy, buzzing, distorted. Not robotic - the Archaeans can mimic inflection and tone - but strange, otherworldly. Sometimes, for no reason, they make musical sounds. Deep bass rumbles, whistles like flutes, staccato ear-bursting drum-beats of solid air. They will save and replay fragments and turns of phrase; they might answer your questions in your own voice.

And slow. Very slow. A short conversation can take twenty minutes. A long one can take days, especially if the Archaean needs to consider something. They have all the time in the world.
Peter Mohrbacher
Who Are You?

They don't quite understand people. They speak to you like they are speaking to a committee. Everything and everyone is plural. They might ask your arms to confirm a difficult climb, your liver its state and health. Your heartrate rises; it asks your heart if it has any objections.

An Archaean is a colony creature. So are you. Long ago, our ancestor cells ate another kind of cell. Mitochondria live inside us, but they don't share our DNA. Similarly, we rely on gut bacteria to digest certain types of food.

But Archaeans are aware of their own composite nature. They ate and integrated thousands of chemical pathways. Cells that can eat sulphur lie dormant, fed by cells that eat iron. In an iron-rich environment the situation is reversed. Humans can survive on a very limited number of foods. Archaeans can eat nearly anything and survive nearly anywhere. The cost of such adaptability is speed. It can take several days to adjust to a new food source.

Luckily almost nothing eats them. A calcinated cancer bear might blunder into one, thinking it is a lantern, but Archaeans are sturdy and toxic. They can always just walk away or sink into the rock, pouring into microscopic fissures and flowing down to their unknown homes. Sentient races treat them like weather; ignore it if you can, use it if you are able to, but don't try and get in the way of a tornado.

Archaeans are toxic. They shed cadmium, lead, mercury, and arsenic like humans shed skin cells. Medieval medicine can't tell you while your hair is falling out and your hands are shaking after spending a few days around an Archean, but they smell like bad news.

Each full day spent in prolonged contact with an Archaeans inflicts 1d6 Constitution damage. The GM may choose to record this secretly and inflict diseases, cancers, palsies, and hair loss as needed. Maintaining a safe distance (30' at least) and limiting contact helps.

They don't want to kill you. They are sympathetic, in the way that a hiker avoiding a patch of wildflowers is sympathetic. 

"They do not fully understand what death is and this makes them dangerous to be around." - Fire on the Velvet Horizon, p.95

If you die, an Archaen might tend to your body. Unless convinced not to, it will ask your gut bacteria and skin mites to take over, like an crisis manager promoting interns to ministers. It might take years, but it will return you to a semblance of life and set you loose, pleased that it was able to assist an injured friend.
Thomas Wievegg

OSR Radiation Chart

Based on fuzzy memories of something from Delta Green (I think).

Save vs. Constitution at the end of every test interval or suffer the effects listed. Effects are cumulative. If you fail a test from a High Intensity source, you suffer the effects from the High, Medium, Moderate, and Low Intensity sources all at once. Radiation is awful.

Test Interval
Atomic bees, cursed metal nuggets.
30 Days
Rashes, headache, dry and flaking skin, nausea, diarrhea, minor hair loss.
Angry Archaeans
7 Days
Nausea, weakness for 2d6 hrs. If >9 hrs, Save or develop cancer.
Archaean Snail-Reactors.
1 Day
Violent nausea, weakness for 2d6 days. Also take 1d6 damage. Body becomes a low intensity radiation source for duration. Also, Save or go blind for 1d6 days. 
Cursed Metal Golems, Archaean snail-reactors cores. 
1 Hour
Take 1d6 damage. 1 permanent damage to all stats. Blind 1d6 weeks. Hair falls out in clumps. Save or permanent sterility. Save or terminal cancer. Body becomes a moderate intensity radiation source for duration.
Skull Totems.
1 Minute
Take 1d6 damage. Blind and sterile permanently. 1d6 permanent damage  to all stats. Even if survived, massive medical attention required to avoid messy death in 1d6 hours.
Atomic beehive core, Archaean weapons.
10 Seconds (1 round)
Movement or action impossible. Pain is horrifying. Skin begins to slough off. Death immediate death in 1d6 rounds.
Russell Jones

Tools and Artifacts

1. Snail Reactors
Huge metal shells, coiled like a nautilus, plated in fantastic metals. Devouring water, spraying steam, humming quietly in the dark. Long ropes of braided copper, coated in ceramics, snake into the rock. They are full of lightning.

Peel the ultra-fine mesh from the mouth of the snail shell and throw a sturdy rock or a piece of iron inside. Then run. Once the shrapnel has cooled, collect the metal fragments and run again. Any metal that stays warm to the touch after a few hours should be thrown away. Cursed Metal is hateful, lead-like metal, warm, and malicious.

2. Cursed Metal Nuggets
Carried by some Archaeans like jewelry or possibly food. They sometimes seem to excrete or devour them. Grey cylinders or rings of lead-like metal. Faintly warm, very heavy. Beloved by alchemists; deadly to everyone.

3. Cursed Metal Golems
Possibly a war-form of Archaeans or a thing they created to deal with difficult problems. A 9' tall screaming sodium-and-uranium behemoth does tend to solve a lot of problems. They sometimes boil out of the rock when Snail Reactors are looted or Atomic Bees are disturbed, kill everything biological or supernatural or annoying in the area, then disappear. If you see burnt shadows on walls and molten footprints, run the other way.

4. Rust Monsters
Symbiotic with Archaean bacteria. A fringe part of their ecosystem, pigeons to humans. When people started smelting iron ore into delicious concentration iron swords and tools, rust monsters migrated upwards. There are still plenty in the Veins, chewing quietly on rocks. Archaeans sometimes feed them.

5. Skull Totems
When an Archaean really doesn't want non-Archaean creatures in an area, it sets out a skull totem. Carved elaborately and with exacting detail to match the skull of a local creature, but made from pure cursed metal, the skull totem emits a horrible aura of death. Anything within 10' suffers Acute Intensity radiation, 10'-20' High Intensity, 20'-30' Moderate Intensity, etc. Stealing one and throwing it at your enemies is a viable, if suicidal, plan. Luckily the Totems only last 1 year.

6. Archaen Weapons
The stuff that empires are made of. They look like musical instruments mixed with off-casts from a glassblowing factory staffed by lunatics with the hiccups. Each one is unique. The effects are devastating. You need to kill a lot of Archaeans to get them to bring a weapon into the Veins.

At a minimum, an Archaean weapon casts a 60' cone or line of Fatal intensity radiation. It also sets everything on fire, including stone. Other effects could include:

1. Boiling clouds of chlorine gas.
2. Slivers of frozen mercury.
3. Nuggets of burning carbon and antimony.
4. Temperature drop to well below zero.
5. Spirals of molten gold.
6. Sonic waves strong enough to shatter bones.

Obviously, being hit with an Archaean Weapon is invariably fatal. Looting one, or getting the Archaeans to use one on your enemies, is much more sensible. A looted weapon has 1d6 uses remaining and is a Medium radiation source. Anyone who knows what it is will kill you to get it, or offer unimaginable wealth or impossible favours in exchange.
Source unknown

Archaean Plot Seeds

1. You find one Archaean standing over the bubbling corpse of another. "Find who did this," it says, and hands you a ticking, buzzing device. It ticks louder the closer you get to the irradiated murders. If you return with their bodies, the Archaean promises to give you their weight in gold.

2. A silver-grey spire has grown into a village and is spraying poison gas everywhere. The villagers want you to find an Archaean and ask them to turn it off.

3. A Volume-Lord is holding an auction. They somehow managed to capture an Archaean in a spell-cage. The PCs, as outsiders, might be trustworthy enough to guard the cage.The Archaean will speak to them by pulsed radio waves that set their daggers and swords humming like struck tuning forks.

4. There is a monastic cult in the Veins that feeds Archaean radicals surface books and poetry. They wear sealed leather suits with lead inserts. They will transcribe your stories and experiences and then, very patiently, read them to Archaean visitors. In return, they will pay you in lumps of gold and platinum. Skilled storytellers will be invited to stay.

5. You find an Archaean transporting metal spheres. It politely informs you that a wealthy volume-lord has traded occultum for chemical weapons. The gas inside the spheres will poison a city; can the PCs steal them, divert them, or make a better offer?

6. An Archaean has made a deal with a Medusa to petrify particularly interesting people. The PCs have to convince the Archaean that they aren't worth turning into statues or offer something better.


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  1. So if you fail to roll under constitution due to exposure to a medium intensity of radiation how long is the duration of you being a low intensity source of radiation?

    1. The same duration as your nausea and weakness (2d6 days). In theory, if that was 7 or more days you'd need to test for exposure to a low intensity source. In practice, I'd worry more about your teammates or healers.

  2. Sets everything on fire + rapid temperature drop = rapid heat expansion and contraction. Very very fun. Will you do silichominids?

    1. I figure silichominids and archaeans are - conceptually - the same kind of thing. You can't really describe them to medieval PCs in ways that are sufficiently different. I'm mashing them together.