The Defenders Almanac RPG features extensive reproductions of in-world documents such as histories, maps, botanical guides, short stories, and diagrams that are all paired with evocative illustrations. The final section of the book details the complete rules for a bespoke and streamlined roleplaying game system designed for quickly diving into short stories of sabotage, rescues, escapes, espionage, heists, and other forms of clandestine resistance.

This stand-alone role-playing game and guidebook vastly expands and elaborates on the conflicted world of the Commonwood, first introduced in the cooperative board game Defenders of the Wild.

Each story requires a storyteller and 2 or more players to roleplay as the main characters: animal Defenders embarking on a pivotal and life-changing mission in the war against the machines. Players build their characters using a character web that expands as the story progresses unlocking new proficiencies and unique abilities. Significant actions are resolved using six-sided dice and the average story lasts 3-5 chapters that are each approximately 1 session of gameplay.