Deep in the Mindspin Mountains, a storm giant warlord known as the Storm Tyrant has seized control of a cloud castle and an Orb of Dragonkind, and is gathering an army of giants from across western Avistan — first to bring the orc hordes of Belkzen under his banner, then to conquer the neighboring realms. Heroes defending the human town of Trunau from an orc raid discover that the attack is just a precursor to the Storm Tyrant’s larger plans.

Working their way through an abandoned border fort, an ancient giant temple, the tomb of an undead frost giant, and an elite fire giant training facility beneath a dormant volcano, the heroes eventually take the fight to the Storm Tyrant himself inside his flying fortress. Can the giant army be defeated before it can conquer the human lands of the Inner Sea, or will all of Avistan bow down in fealty to the Storm Tyrant?