# Mothership to Cairn conversion
**URL:** https://discourse.rpgcauldron.com/t/mothership-to-cairn-conversion/3663
**Category:** Play
**Tags:** conversions, tools
**Created:** [August 10, 2026, 12:32am UTC](https://discourse.rpgcauldron.com/t/mothership-to-cairn-conversion/3663 "2026-08-10T00:32:24Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@rolledlow](https://discourse.rpgcauldron.com/u/rolledlow)
#### Post date: [August 10, 2026, 12:32am UTC](https://discourse.rpgcauldron.com/t/mothership-to-cairn-conversion/3663/1 "2026-08-10T00:32:24Z")
I’m a big fan of not reinventing the wheel.
Has anyone written about converting from Mothership to Cairn? I’m reading the advice in the Warden’s Guide while hoping someone smarter than I has given this some thought.
Specifically, I’m looking at _Desert Moon of Karth_ and _Wages of Sin_ for a western inspired setting.
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### Author:  [@Barnum](https://discourse.rpgcauldron.com/u/Barnum)
#### Post date: [August 10, 2026, 11:12am UTC](https://discourse.rpgcauldron.com/t/mothership-to-cairn-conversion/3663/2 "2026-08-10T11:12:37Z")
👋 I’ll be interested in what you end up doing here. I still havent decided yet whether I was hacking mothership with thematic backgrounds and less horror or converting the material to a new system like you propose.
I think the person to ask is bread wizard (user name on the usual suspects of osr discord servers). He posted that he had used [Monolith](https://adamhensley.itch.io/monolith) (a cairn-like) to play desert moon of karth. He wrote about the experience [here](https://sky-spire.bearblog.dev/review-37-desert-moon-of-karth/) and might be willing to share his notes.
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### Author:  [@yochaigal](https://discourse.rpgcauldron.com/u/yochaigal)
#### Post date: [August 10, 2026, 12:56pm UTC](https://discourse.rpgcauldron.com/t/mothership-to-cairn-conversion/3663/3 "2026-08-10T12:56:40Z")
@bread_wizard is indeed here!
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### Author:  [@bread\_wizard](https://discourse.rpgcauldron.com/u/bread_wizard)
#### Post date: [August 10, 2026, 8:55pm UTC](https://discourse.rpgcauldron.com/t/mothership-to-cairn-conversion/3663/4 "2026-08-10T20:55:02Z")
Yes, and I absolutely remembered that I had set up an account here!
Here are my rough and ready conversion notes for Desert Moon of Karth-- most of these I just cribbed from the Monolith bestiary, finding “similar enough” stat blocks for the basic stuff in the adventure. I also borrowed the “Stress Outcomes” from Liliputian to simulate a Mothership stress roll.
> **[Desert Moon of Karth](https://docs.google.com/spreadsheets/d/19P6KnNarQhj2ecoQYkuYGbzfycak2G3sAVveFoNd91c/edit?usp=sharing)**
>
> This Sheet is private
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### Author:  [@rolledlow](https://discourse.rpgcauldron.com/u/rolledlow)
#### Post date: [August 10, 2026, 9:39pm UTC](https://discourse.rpgcauldron.com/t/mothership-to-cairn-conversion/3663/5 "2026-08-10T21:39:08Z")
Ooh! Thank you. I’ll put this to good use!
After I finally wrapped my brain around the Mothership stat block, it‘s not terribly difficult. I was weirded out by the minimal one-line stats in percentages. I guess being weirded out is appropriate for a system used for creepy horror. LOL.
Anyhow, I’m cribbing this. I’ll share whatever I end up with. Much appreciated!
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### Author:  [@oldscratch](https://discourse.rpgcauldron.com/u/oldscratch)
#### Post date: [September 20, 2026, 9:06am UTC](https://discourse.rpgcauldron.com/t/mothership-to-cairn-conversion/3663/6 "2026-09-20T09:06:25Z")
The Monolith 2e public playtest is available here.
> **[Monolith 2nd Edition (Player's Guide - Playtest)](https://docs.google.com/document/d/1ClBpfsAUJSzWLCoM7A9RSegOo3yrLh5XXKzsrpgaJBc/edit?usp=sharing)**
>
> Monolith 2nd Edition (Player’s Guide) Public Playtest: Beta Version 1.1 Updated: September 17, 2026