Beneath the sands of Mongolia's Gobi Desert lurks the Olgoi-Khorkhoi—a deadly worm said to kill on contact and shoot electricity at its prey. Nomads still fear speaking its name.
Olgoi-Khorkhoi. In Mongolian, it means "intestine worm." Not the most elegant name, but among the nomads of the Gobi Desert, it is spoken with genuine dread.
Beneath the vast sand seas of the Gobi, this creature is said to dwell. Between one and 1.5 meters long. As thick as a human arm. Dark red, with no discernible head or tail. No visible eyes. No visible mouth. It looks, by all accounts, like a giant living intestine writhing through the sand.
But its appearance is not what makes it terrifying. Its killing power is.
According to Mongolian tradition, the Death Worm kills in two ways.
First, contact poison. Anyone who touches the worm—or its bodily fluids—dies instantly. Metal objects that come into contact with the creature reportedly turn blue.
Second—and this strains credulity even further—the worm can project some form of electrical discharge at a distance. Humans and livestock standing several meters away suddenly collapse and die. Nomads describe it as "something flying through the air."
The Death Worm was first introduced to the Western world by Czech paleontologist Ivan Mackerle, who visited Mongolia in 1926 and documented local testimonies.
According to his reports, sightings concentrate in June and July, when the sand reaches its peak temperature and the worm allegedly rises near the surface. It is also said to appear more frequently after rain. Notably, it is often spotted near the parasitic plant goyo (Cynomorium songaricum).
What makes Mackerle's account particularly striking is that he heard about the creature directly from the Prime Minister of Mongolia. The Prime Minister himself had not seen the worm, but he did not doubt its existence.
Since the 1990s, multiple expeditions have ventured into the Gobi in search of the Death Worm.
In 2005, British researcher Richard Freeman led a team on an intensive survey of the southern Gobi. They did not find the creature, but they collected numerous detailed and remarkably consistent eyewitness accounts from local inhabitants. What struck the researchers most was that the witnesses had no interest in fame or reward. They spoke of the Death Worm out of pure, unaffected fear.
A New Zealand television crew conducted another search in 2009, again without locating the animal.
Proposed explanations for the Death Worm include a large desert-adapted lizard, a sand boa, or an unknown amphibian species. The electric discharge claim is widely regarded as the least plausible element—organisms like electric eels require aquatic environments, making a desert-dwelling electric creature extremely unlikely.
But the Gobi Desert spans 1.3 million square kilometers of barren terrain. Much of it has never been surveyed by modern science. What lies beneath the sand remains largely unknown.
The Mongolian nomads have a warning: "Do not touch anything yellow." Where the goyo flower blooms, death may be waiting just below the surface.
