"The frame of the doorway that led into this inner chamber was one of the most extraordinary architectural compositions ever conceived by the Classic Maya. A Cosmic Monster, representing the arching body of the Milky Way in its east-west configuration, frames the door in such deep relief carving that it seems to be writhing out of the wall. The front end of the monster takes the shape of a crocodilian head and is decorated with the symbols of Venus. Pointing west, the counterpart in the sky of this great crocodile parallels the ecliptic so that planets often travel along its belly following the path of the sun. At the opposite end, the sun-marked plate of sacrifice that sits on the junction of the Milky Way and ecliptic rides the tail of the monster.
In the great lazy-S scrolls composing its arching, serpentlike body cavort the beings who have been conjured up by the bloodletting rituals inside the sanctum. These particular scrolls are clouds. For the Maya, clouds of light in the night sky constitute one perception of the Milky Way. Clouds as metaphors for the heavens still prevail among some modern Yukatek shamans. Clouds, rain-laden, celestial, or in the form of sweet incense smoke, harbor ch'ulel, the soul stuff of the living universe...Here at Copan the beings conjured up in the clouds are spirits called way or nawal and the serpent-footed god, K'awil--all beings that the king called upon in the exercise of his power."
Freidel, Schele, Parker, Maya Cosmos: Three Thousand Years on the Shaman's Path, p. 151