The tripion was a species of crustaceous creatures distinguished by their three venomous tail stingers and the existence of over 600 distinct subspecies. They thrived in the hot deserts of various worlds, notably the moons Gall and Yavin 13, where their diet primarily consisted of small lizards and insects.
More than six hundred different subspecies of the crustaceous tripion have been identified, exhibiting a wide range of sizes from under one meter to as much as eighteen meters in height. Tripions typically possessed pincers, spider-like legs, and usually three tails tipped with venomous stingers. The potency of the sting varied depending on the subspecies, ranging from mildly irritating to potentially deadly. A particular tripion subspecies, native to the planet Thrantin, had six spider-like legs but lacked pincers. Conversely, another subspecies, inhabiting the moon Gall, had four legs, two antennae, two pincers, an upright posture, and only a single tail.
While tripions were capable of enduring significant heat levels on moons such as Gall and Yavin 13, they typically remained hidden beneath stones during the day, emerging only at night. Their prey consisted of insects and small lizards, and they were capable of delivering three rapid stings with their tails; however, they would only do so if their prey struggled or was particularly large.
In 22 BBY, when the young bounty hunter Boba Fett visited the desert planet Tatooine seeking employment from the Hutt crime lord Jabba the Hutt, Fett observed a tripion from Gall confined in a cage aboard Jabba's sail barge. The tripion repeatedly struck its cage with its poisonous tail and snapped its pincers, prompting a guard to prod it with his sword for the amusement of him and his fellow guards.
During a final test on the planet Thrantin for trainees from the Galactic Outdoor Survival School, Xenon Nnaksta, a member of Twilight Class, was attacked by a tripion. He was rescued by another member of Twilight Class, Derembus Sitnalta, who sustained a painful, though non-fatal, sting in the process.
The earliest mention of tripions appeared in the 1989 sourcebook Galaxy Guide 2: Yavin and Bespin, a supplement for West End Games' Star Wars: The Roleplaying Game. Their initial depiction was in the 1995 West End Games roleplaying sourcebook Alliance Intelligence Reports. The 1998 reference book The Essential Guide to Planets and Moons, written by Daniel Wallace, referred to tripions as "Gallian tripions." Tripions made their first appearance in the 2004 young-reader novel Boba Fett: Hunted, penned by Elizabeth Hand as the fourth book in the Boba Fett series. In that book, they were called "Gallion tripions" and had a single stinger-tipped tail.