With danger close behind, the Broken Tusks journey through the bountiful but treacherous Lost Mammoth Valley in search of the Primordial Flame. The Tusks' scouts solve the riddles of the primordial valley and recruit a motley league of unlikely followers, all while evading the watchful gaze of the vale's villainous overlords. In order to fulfill their quest, the scouts must ultimately go toe to toe with these vile masters: a vicious white dragon, a sadistic necromancer, and a boarish beast-god. "Lost Mammoth Valley" is a Pathfinder adventure for four 4th-level characters by Jessica Catalan. This adventure continues the Quest for the Frozen Flame Adventure Path, a three-part monthly campaign in which the heroes lead a band of nomadic hunter-gatherers across a brutal primordial landscape. This adventure also includes an examination of megafauna, including advice and rules for creating your own new giant animals; a glossary of Mammoth Lords' depictions of Golarion's most popular deities; and new prehistoric creatures to befriend or bedevil your players. Each monthly full-color softcover Pathfinder Adventure Path volume contains an in-depth adventure scenario, stats for several new monsters, and support articles meant to give Game Masters additional material to expand their campaign. Pathfinder Adventure Path volumes use the Open Game License and work with both the Pathfinder RPG and the world's oldest fantasy RPG.