The fiercest surprises often come from the most familiar foes! Just as no single class description can define every fighter, rogue, or wizard, no single creature entry can truly cover every vicious champion, unholy priest, or savage sorcerer in a band of organized and intelligent monsters. With Pathfinder Roleplaying Game: Monster Codex, fleshed-out hordes are at your fingertips! This volume presents a trove of entries for 20 classic monster races, giving you new ways to use your favorite monsters in a variety of encounters and challenge levels. Pathfinder Roleplaying Game: Monster Codex is an indispensable companion to the Pathfinder Roleplaying Game Core Rulebook and Pathfinder Roleplaying Game Bestiary. Pathfinder Roleplaying Game: Monster Codex includes: * Pages upon pages of specialized entries for 20 classic monstrous races, from goblins and drow to kobolds and trolls. Face off against such formidable foes as gnoll packlords, ratfolk sages, and dinosaur-riding lizardfolk champions! * Detailed information on the ecologies and societies of these formidable creatures. * New feats, equipment, spells, and archetypes to help you customize all 20 monstrous races-and the adventurers who fight or trade with them. * A horrific new monster associated with each race-allies, thralls, and variants. * Sample encounters ready to challenge raw recruits and experienced adventurers alike. * ... and much, much more!