Hearts of sacrificed victims were p

Hearts of sacrificed victims were placed on the belly of the chacmool, a Tula invention. The chacmool is a sculptural figure lying down facing up, legs drawn in, elbows on ground, with its upper back raised, head turned to a near right angle. He holds a vessel, disk, or plate on his stomach, where offerings may have been
placed or sacrifices carried out. Although the complete origins of the chacmool are still undetermined, they proliferated from Tula times. Twelve have been found at Tula, fourteen at Chichen ltza, and two in the Aztec capital, Tenochtitlan.