Youaltepuztli — "Night Ax": one of Tezcatlipoca's guises. People would hear the sound of an ax hewing into the trees in the forest at night, and if they so dared to investigate, would find this headless corpse with two doors in its chest opening and shutting. It is the doors that make the sound of the ax. If you can reach in and grab its black heart, you can demand some sort of ransom from the demon. According to the folklore, Youaltepuztli is hard to catch.