Izirion's Enchiridion of the West Marches is a campaign guide written for running "West Marches" style games, which are large, open-ended sandbox campaigns. West Marches-style games have no set plot and feature a large roster of players; those players decide their own adventuring parties and their own mission objectives, leading to strongly player-driven adventures.

Within its 126 pages, the Enchiridion contains: rules and procedures for wilderness survival and exploration; guidelines and toolsets for generating your own West Marches; theory and advice on emergent narrative and environmental storytelling; and a collection of feats, magic items, and additional content for DMs to use in their games.

The Enchiridion raised over $28,000 on Kickstarter and is a Silver-Tier bestseller on DriveThruRPG.