Out now: Madness at Geneva Lake for Call of Cthulhu

The Madness at Geneva Lake is a Call of Cthulhu adventure that weaves a little-known chapter of TSR’s history into a tale of cosmic horror!

First released at Gary Con 2025, this dread tale by Alyssa Faden and Gary Con founder Luke Gygax is set in 1891 on the snow-dusted shores of Lake Geneva Wisconsin.

Get your copy today at DriveThruRPG: available in PDF and Print.

Brilliantly weaving a little-known chapter of TSR’s history into a tale of cosmic horror, this scenario blends Chaosium’s mastery of Lovecraftian storytelling with Lake Geneva’s rich roleplaying legacy.

Gary Con founder Luke Gygax said, "Gary Con is a memorial convention that celebrates my father’s legacy and the enduring passion of the gaming community he helped create through Dungeons & Dragons. This year’s partnership with Chaosium as the Premier Sponsor of Gary Con feels like a convergence of history and creativity, bringing together two pillars of the RPG world to honor their shared dedication to immersive storytelling and imagination."

A joint creative venture by GaxxWorx and Chaosium.