Based on primary data and analyses from the Moon Pyramid Project at the center of the UNSECO World Heritage site at Teotihuacan, Mexico (1-550 CE), Animal Matter questions how the inhabitants of this ancient metropolis elevated a monumental earthwork into a sacred mountain that crowns one of the most influential and enduring ritualized landscapes in Mesoamerica. The research gathered from four dedicatory caches embedded within the Moon Pyramid constitutes one of the best-attested cases of mass animal sacrifice within Mesoamerica, with over 200 animals offered as primary sacrificial victims or secondary products (ritual paraphernalia, isolated body parts, etc.). By bringing biographies of jaguars, pumas, wolves, rattlesnakes, and golden eagles to life, the book supports the earliest evidence for wild carnivore management in captivity within the city confines, a feat unknown in this region for ten centuries until it appeared in detailed and lurid colonial descriptions of Moctezuma's zoo. The book argues that state-sanctioned ritualized performances were sacred places to stage the consecration of apex predators into key symbols of the Teotihuacan state. Perfected through sacrifice into the heart of the monument, their essence animated the Moon Pyramid into the material nexus of state authority: a sacred mountain. By utilizing the tools of relational ontologies and new materialism, and applying them to her non-human subjects, Sugiyama offers a unique perspective on their roles in the development of state sovereignty. The result is a rigorously argued description of ancient state-coordinated rituals—spectacular but full of imperfections and contradictions—an approach that humanizes the past.