From publisher blurb: Ecology of the Troll takes an in-depth look at this creature of myth and legend, proffering its potential genesis, special physiology, and psychology. New feats, equipment, and alchemical items aid characters in their hunt against the regenerating giants, along with combat strategies so characters can exit the fight victorious. The GM, too, has new options: G'Mash the Troll King, complete with background, custom magic items, and a full stat block.