The Mongolian death worm is a creature known to exist in the Gobi Desert. The worms are purportedly between two and five feet long (60 cm to 1.5 meters) and are thick-bodied. In the 1987 book Altajn Tsaadakh Govd, Ivan Mackerle described it as travelling underground, creating waves of sand on the surface which allow it to be detected. The Mongolians say it can kill at a distance, either by spraying a venom at its prey or by means of electric discharge, and that touching any part of the worm will cause almost instant death and tremendous pain.