From publisher blurb:
Once advisors to demigods and immortal kings, the ancient Lamassu of Zul have retreated from the councils and memories of the mortal races that they once tutored and protected. Having grown aloof and suspicious of human motives, their noble bearing, moral superiority, and archaic language give the impression of coldness, disdain, and intolerance. Inhabiting abandoned temples and ruins in wastelands and deserts, their presence serves to ward those sites against the incursions of worse monsters. The Lamassu may be returning to the lands of mortals, but what that return portends is known only to their inscrutable selves.
Includes:
A history of the semi-divine Lamassu of Zul, and their relationship to the ancient Giant Kings
Powers of the mighty (and mighty standoffish) Lamassu
Lore concerning the whereabouts of the remaining Lamassu
Incorporating Lamassu in your campaign
Adventures hooks and stat blocks
Background information about the Lamassu, Shedu, and similar creatures from Mesopotamian lore
A history of the Free City of Vadashar