Has two versions- this one for Pathfinder and Fey Folio: the Unseelie Court for D&D 4E. This latter version received an ENnie honorable mention.
Publisher Blurb:
Nearly 20 new monsters for pathfinder roleplaying game! A baker's dozen of new fey species inhabit these eldritch pages, waiting to pester, infest, and perhaps even eradicate your adventuring party. Each fiendish fey is beautifully color illustrated with all original art by the talented Vasilos Zikos.
Fey are embodiments of emotion, and wicked fey are cruelty, lust, anger, and mischief given form. From the frightening dullahan dreadknights to the malicious vodnik bog troll, these pages offer forth the most dangerous the Fey Realm has to offer- not the mindless beasts or wild spirits, but the cunning and cruel twisted fey races, the clans of the Fey Realm.