From publisher blurb:
The Pathfinder Roleplaying Game greatly expands the options for barbarian PCs over earlier iterations of the game. Rather than a simple boost to hit points and melee damage, the new barbarian also gains special abilities when he releases his inner fury. Brutal Barbarians expands the class even further.
More than just a list of additional rage powers, this supplement presents a new type of rage, an alternate class, and new class abilities suitable for wilderness survival. The new barbarian bloodline option allows a barbarian to acquire specific rage powers inherited from a monstrous ancestor. Several new rage powers and 25 feats are also included, including a few designed for barbarians who fight from horseback.