Source: WTL© digital photograph (2009) taken on site at the Templo Mayor, Mexico City.
Comments: This platform, belonging to the seventh and last phase of construction of the Templo Mayor, was excavated in 1948, and these polychrome serpents heads were also found in the location you now see them. (Incidentally, the high-angle photographs of #1 and #2 in this series were taken from a terraza in a building just to the left of the one you see in the background of this photo.)
Humanities Question: What is the name and what are the main characteristics of the Aztec god represented by this plumed serpent heads?