Mithra sacrificing the bull, assisted by Cautès and Cautopatès (Mithraeum in Palazzo Barberini)

In the center of the fresco, Mithra wearing the Phrygian cap grabs the bull by its nostrils and kills it by puncturing the jugular artery with a dagger. A snake and a dog drink the spurting blood, while a scorpion bites the bull's testicles. Above, the celestial vault is represented by the twelve signs of the zodiac. At the center of the arc they form, a lion-headed god rests his feet on a globe. He is wrapped in the rings of a serpent.
Under Mithra killing the bull, his two assistants Cautès and Cautopatès each brandish a torch, one upward, the other downward. Around the main scene, ten panels illustrate the story of Mithra. Left: Zeus slaying the Giants, the birth of the god from a rock, Mithra spouting water from the stone by striking it with an arrow. Right: the god carrying the bull, the mystical banquet, the pact with the Sun and initiation into the cult of Mithra.