Faerie Mysteries (Pathfinder Second Edition)

Explores the influence of fey creatures and the faerie realms on a Pathfinder Second Edition campaign world. It is not so much about monsters and magic as it is about how the influence of the fey can change the feel and flow of a campaign, and it gives you a game-mechanical system for describing and representing that in-breaking of raw, untamed, primal magic that make the fey what they are.