OS-SIX

A free, open-source, and modular D6-based TTRPG system

Welcome to OS-SIX

Produced by Alchemy GameLab

Written by Beren Goguen

All you need to play:

  • Your unbridled imagination

  • 3 - 6 people

  • A handful of six-sided dice

  • Pencils and paper

OS-SIX is a lightweight, modular table-top RPG system that anyone can use and modify (see SRD info in the FAQ for details). This game was designed with one primary purpose in mind: flexibility.

Teach anyone to play in 30 minutes and roleplay almost any setting imaginable, from gothic horror to weird west to crime noir.

How is this possible? Modules!

In addition to the free Core Rules, this system also includes several different modules that you can mix and match to create the game world you’ve always wanted to experience!

Cowboys vs. aliens? Mobsters vs. vampires?

Mobster vampires… ?

With OS-SIX core rules, modules, and random tables, you can let your imagination run wild!


CONTENTS


FAQ + Info

  • This license allows anyone to make games using the OS-SIX Core Rules to either publish it for free or sell it, without permission from Alchemy GameLab. Just a few basic rules:

    CONTENT

    1. If you adhere to these terms you are allowed to publish free or commercial material based upon and/or declaring compatibility with OS-SIX without express permission from Alchemy GameLab.

    2. Art and text from our publications may not be reused or translated, unless you have our explicit permission. This does not include the OS-SIX Core Rules—which may be copied, modified, and distributed according to CC0 Public Domain. No attribution required (but you're welcome to thank Alchemy GameLab in your acknowledgements if you wish).

    3. The mechanics and game rules of OS-SIX may be reused and referenced freely.

    BRAND

    4. Your product cannot use the Alchemy GameLab or OS-SIX logo unless you have our explicit permission.

    5. You are allowed and encouraged (but not required) to use the text: “Compatible with OS-SIX.”

    6. You’re not allowed to give the impression that your product is an “official OS-SIX product” or that Alchemy GameLab endorses or sponsors you in any way without express permission from us.

    LEGAL

    7. Alchemy GameLab takes no responsibility for any legal claims against your product.

    8. Any legal disputes, controversies or claims related to this license shall be governed by and construed in accordance with United States law.

    9. The following text must be included in the legal text, somewhere visible in the publication, and on the product website or storefront:

    “[Product name] is an independent production by [Author/Publisher] and is not affiliated with Alchemy GameLab. It is published under the OS-SIX SRD License.”

    10. This text must be legibly included somewhere in the product and on the storefront:

    “OS-SIX is copyright Alchemy GameLab.”

    Basically, you can use, modify, reprint, republish, and do whatever you want with the OS-SIX Core Rules that you want. This also includes the free Core Modules. Other modules and games created using the OS-SIX SRD (i.e. games built using the OS-SIX rule system) are not included as part of this License and therefore are not covered by the CC0 Public Domain license.

  • It’s in the works! While in beta, OS-SIX will not have a PDF or print version. However, we hope to release a free “bare bones” PDF in mid 2025 and a print-on-demand “Full Version” (with art) on DriveThruRPG by late 2025. So stay tuned!

  • We plan to offer a paperback print-on-demand “Full Version” (with art) on DriveThruRPG by late 2025. So stay tuned!

  • There are other TTRPG games that use similar mechanics to OS-SIX. There are also other games that just use D6. However, as far as we know, OS-SIX is the first free, open-source, and setting-agnostic D6-based TTRPG system with a CC0 license and SRD that anyone can use and modify. It’s also the only “modular” D6 system that we know of. With modules, you can plug, play, mix, and match genres and settings with ease.

    Our intent with OS-SIX is to give something back to the gaming community with no strings attached. If you love it, be sure to check out some of our other games built using this system. But ultimately, we just want people to play it and have fun with it.

  • This game would not exist without the inspiration and influence of several other amazing TTRPG games, including:

    • Mork Borg by Pelle Nilsson and Johan Nohr

    • Blades in the Dark, by John Harper

    • Apocalypse World by by D. Vincent Baker and Meguey Baker

    • Mothership by Sean McCoy

    • And of course the OG: Dungeons and Dragons by the legendary Gary Gygax and Dave Arneson

  • A big thanks to my extended gaming family and friends:

    Mark, Jacko, Kevin, Caleb, Simon, Adam, Nate, and Hazel