As the eighth of the Yohualteuctin, Tepeyollotl governs every ninth date from day eight of the tonalpohualli onward, his recurrence moving independently through the twenty day signs and thirteen trecenas in the same manner as the other eight, realigning with the full count only after 2340 days. A date under his night was read, in the layered method the tonalpouhque applied, as carrying the jaguar's severity and the cave's hidden depth, a reading consistent with Tezcatlipoca's own reputation across his several aspects as an unpredictable and testing power, one Sahagun's informants approach with more caution in their commentary than they show toward the gentler night lords such as Piltzintecuhtli or Chalchiuhtlicue.
The echo that Nahua thought attributed to him, the mountain's own voice answering a call sent into its caves, gave Tepeyollotl a mythic explanation distinct from the plain arithmetic that otherwise governs the night lord sequence, and this is one of the few night lords for whom the sources preserve a specific natural phenomenon read as his direct presence in the world beyond the calendar itself. His position just before Tlaloc, the rain god who closes the sequence as ninth, places two deities connected to mountains, caves and the sources of water immediately adjacent at the sequence's end, mirroring the pairing of fire and blade that opens it with Xiuhtecuhtli and Itztli.
Sources Cycles of Time and Meaning in the Mexican Books of FateElizabeth Hill Boone with Florentine Codex: General History of the Things of New SpainBernardino de Sahagun; translated by Arthur J. O. Anderson and Charles E. Dibble