Although humans and nahualis shared a single soul but lived separate lives, people with magical powers could merge with their nahualis, assuming purely animal form, usually for specific magical purposes. Gods could do the same with their nahualis. The god who took most advantage of this capability was Tezcatlipoca, the sorcerer god. His name means Smoking Mirror, after the obsidian mirrors used in scrying. He could also bear the name The God Over Your Shoulder, the one who whispers crazy things in your ear, urging you to put your hand in a fire or to jump off a cliff as easily as suggesting that you create something magnificent or do something heroic. In our contemporary pseudo-scientific mythology, he approximates the Id, particularly when compared to Quetzalcoatl, who resembles the Super Ego. These gods can act as opposites, but they can also form a nahuali pair. Both are creator gods, and each depends on the other, each supplying something that the other lacks. Both gods share avatars and nahualis: perhaps the most important being Mimixcoatl and Tepeyolotli — in fact, through these nahualis either god can transform himself into the other. At the right of image 4, we see an anthropomorphic Quetzalcoatl. At left is the jaguar god, Tepeyolotli. Jaguars are solitary, often nocturnal hunters, possessing incredible strength and incomprehensible ferocity. They can travel fast and are strong swimmers, seeming to delight in water. The fluidity of their movement suggests stealth and enchantment. They have a wide vocal range, extending from a roar to a growl to a whisper — to a hiss. Tepeyolotli's name means Heart of the Mountain, a reference to his familiarity with the water the Aztecs thought filled mountains, as it did the chambers in their counterparts in the sky. It also reflects his love of caves and knowledge of the underworld, and his eerie, haunting voice echoed through the valleys and mountains, which the Aztecs took as a particularly powerful omen. A god of darkness, his black spots were dark stars. A jaguar of this type devoured the sun or moon during an eclipse. In image 4, anthropomorphic hands emerge from his fore-paws and a smoking mirror replaces a human foot. This indicates that Tezcatlipoca has merged with his nahuali, Tepeyolotli, and that they both form one animal presence. The two volutes coming from his mouth indicate his decisive but mysterious voice. This is balanced by Quetzalcoatl's shell trumpet, which speaks of order and obligation. Tezcatlipoca-Tepeyolotli's voice dominates this match: here Quetzalcoatl assumes the role of secondary figure, a bearer of offerings, but also a figure that Tezcatlipoca-Tepeyolotli cannot do without.