From publisher blurb:
Since the release of the first bestiary, the first monster book, there have been those who asked - can I play something exotic, can I play a monster instead of a regular character?
In this release of the Monster Classes series, you have the opportunity to play as FOUR different savage races - the hill giant, lizardfolk, troglodyte, or troll! As a member of these savage races, your experience playing in the Pathfinder Roleplaying Game is sure to be unique and filled with unexpected situations.
This book includes four monster classes - the hill giant, lizardfolk, troglodyte, and troll, along with the associated feats necessary to build interesting characters, that at the same time are true to the concept presented in the Bestiary.