Graboids

Graboids are fictional subterranean predators that appear in the Tremors film franchise. Debuting in 1990's Tremors, they are the recurring antagonists around which the series revolves. Across films, graboids inhabit desert and semi-arid regions, where they lurk underground and emerge to prey on living creatures.

Description: Graboids are large, worm-like organisms with elongated, cylindrical bodies. They are covered in tough, leathery skin, vary in color from gray to brown, and lack visible eyes. Their most distinctive feature is a wide, circular mouth lined with rows of sharp teeth.

Senses and movement: They rely on sensing ground vibrations rather than sight. They move by undulating contractions that tunnel through soil, making it difficult to detect them until they strike. They swallow prey whole and can uproot or swallow large animals.

Life cycle and forms: In the film series, graboids can metamorphose when exposed to surface conditions into surface-dwelling forms known as Shriekers, which lack subterranean burrowing capability but hunt on land by heat sensing; Shriekers can further develop into Ass-Blasters, fire-breathing predators capable of flight.

In popular culture: Graboids have become iconic in science fiction and horror, spawning sequels, spin-offs, and a dedicated fan base. The early films are set in Perfection, a fictional desert town in Nevada, forming a recurring setting in the series.