About

Welcome to the Grimoire!

The Mythosan Grimoire is the central hub for the lore, maps, and mechanics of the world of Mythosa. Created and maintained by Bruce A. Gulke, this site is a passion project dedicated to deep, iterative world-building and the classic spirit of tabletop roleplaying games. Over the years, Mythosa has evolved alongside the games played within it. Having originally shifted from D&D 5E to Old-School Essentials (OSE), the setting embraces a distinctly old-school flavor - where classic design philosophies, customized house rules, and rich regional histories take center stage.

What You’ll Find Here
  • The Mythosa Codex & Player’s Companions: Semi-regularly updated resources and PDFs detailing the cultures, organizations, cosmologies, and deities of the world.
  • Handcrafted Cartography: Evolving climate and political maps detailing the realms, from civilization's heartlands to the dangers of the regions like the Unhallowed Wilds and the Eldritch Desolation.
  • RPG Tools & Software: Home to downloads and support for TableSmith, a random table generation tool designed to help Game Masters inject spontaneous flavor into their own sessions.
  • Design Commentary: Occasional deep dives into tabletop game theory, world-building logistics, and why classic systems keep us coming back to the table.
Thank you for visiting!

Last updated: June 16, 2026

Comments

Forticus said…
Great to see Mythosa alive.
Still got PDFs and a map from 2006/7 plus a file from Dec 1993 with a very inspiring email conversation on my computer. Though I can't find the "Mythosa Files" from 1993.
Is there an online community of Mythosa, other than this blog?

Best wishes
p581mao (in 1993)
1:20 PM
Bruce Gulke said…
Hi there!

Thanks for the kind words :) There's a few websites or wikis that use Mythosa (or did in the past), but not much more other than this site.

I have a link to some older PDFs in the comments of the "Downloads" page, but those are from the D&D 3.5 days. Not sure if I have anything from 1993 anymore; if I do I'd have to dig through old archival backups probably :)
10:19 AM
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