From publisher blurb: A race of crafty planetravellers sustained by wealth and bound by their compulsions. A brood of disfiguring parasites that weaponize their hosts and become ravenous titans. A host of angels who descend on evil with the force of shooting stars and leave nothing standing. Creatures from the lightless deep, the realm of dreams, the domain of gods, the artifice of Man and mer. These and more strange and exotic denizens are catalogued in A Certain Monstrous Index. A Certain Monstrous Index contains 25 innovative monsters and monstrous species to shake up your campaign setting. Intrigue, terrify, and empower your players with these remarkable friends and foes. Featuring full-color illustrations, and troop unit rules to simulate a party against an army. This book is 100% compatible with the Pathfinder d20 ruleset, either with the Golarion or Caneis campaign settings.