The pyramid that supported the Temple of Quetzalcóatl boasts a marvellous stone décor highlighting the talud-tablero style. Feathered serpent heads on the tablero (vertical part) alternate with stylised masks of an old water deity (with circled eyes), an ancestor of Tlaloc. Other serpents surrounded by feathers (of quetzal, the sacred bird, or leaves of corn, the mother plant) undulate along the taluds (the sloping part) towards the stairs, whose ramps are dotted with awesome rattlesnake heads.