Armed with explosives, two men are heading to Mongolia's Gobi Desert to find the fabled acid-spitting and lightning-throwing Mongolian death worm.

The worm has never been documented but some Mongolians are convinced it exists. They call it Allghoi Khorkhoi, or "intestine worm" because it resembles a cow's intestine and is about 1.5m long.

The worm apparently jumps out of the sand and kills people by spitting concentrated acid or shooting lightning from its rectum over long distances, NZPA reports. (Seriously.)