"The strangest of all the phantasms described is, perhaps, the Youaltepoztli, literally, "the night hatchet or axe." It manifested itself by causing loud intermittent sounds resembling those produced by the blows of an axe in splitting wood. These ominous sounds were audible at dead of night in the mountains, and inspired terror, for they were said to be illusions produced by Tezcatlipoca in order to frighten and mock those who were out in the dark. When a brave man heard them, instead of taking to flight, he followed the sound of the blows, and as soon as he perceived a semblance to a human figure he quickly ran towards it and seized it firmly. But it was not easy to do so, for the phantom ran to and fro for a long time. At last it pretended to be worn out and stood still, waiting for its pursuer, who perceived that the spectre bore the semblance of a man without a head. Its neck was like a trunk of a tree that has been cut, and its chest was wide open and had at each side what was like a small swinging door that opened and shut as the phantom ran. When these doors closed and met they produced the strange sounds like hollow blows.
"Now if the man in pursuit was a brave warrior or priest, he looked into the opening, and perceiving the heart of the phantom introduced his hand and seized it as though he would tear it out. With this in his grasp he demanded strength and bravery or riches, for it was in the power of Tezcatlipoca to grant anything that was asked for, although he did not dispense his favors equally."**
**This is but one of many fantastic and terrifying creatures of Mexican folklore which can be found in the scholarly paper "A Note on Mexican Folklore" by Zelia Nuttall and published in The Journal of American Folklore, Volume 7-8, 1895. The paper was one of the rich resources I used when doing research for my novel The Flight of Michael McBride and where the Night Hatchet makes an appearance. The rest of Nuttall's paper is terrific, and in one of those wonderful ironies is filled with the carefully annotated notes of a Franciscan monk (in 1529) whose goal was to collect "the superstitions" of the Indians in hopes of stamping them out with the light of Christianity. But the thoroughness and breadth of his notes suggests to me that he enjoyed the tales of these macabre creatures far more than he might admit!
The art here is from a group of spectacular Mexico City based mural graffiti artists -- Sego y Ovbal (at the top), Saner and Sego (immediately above) working on a stunning mural project in Miami and below, another project completed by Sego y Ovbal, (click on the image for a larger version) and you can see much more of his work on this Flicker page, which will tear you away from any other work you thought you ought to be doing. Really.