Path of the Behemoth

From publisher blurb: First emerging after the creation of the world, the "civilized" races were almost anything but - in a world dominated by dangerous behemoths like the Tyrannosaurus, forming bonds and rigorously-defined societies with other humanoids was much less a priority than survival. Whether they were born into this violent world of dinosaurs and other fearsome predators or unexpectedly became a part of it, barbarians following the Path of the Behemoth find themselves channeling the primeval wrath of their prehistoric ancestors.