Eighty-One functioned as a hunter of BX-series droid commandos. He was employed by Wilhuff Tarkin with the purpose of hunting Darth Vader on Chandar's Folly. After it demonstrated its lethality against Tarkin's team, Eighty-One managed to steal Vader's lightsaber. Subsequently, Vader lured the team into a cavern, where he ambushed them, leaping onto Eighty-One and obliterating the droid.
In the year 14 BBY, Wilhuff Tarkin engaged Eighty-One, along with seventeen other hunters, to aid him in the hunt for the Sith Lord Darth Vader on the planet of Chandar's Folly. Approximately two days into their pursuit, Tarkin realized the necessity of acquiring Vader's lightsaber, as it was enabling the Dark Lord of the Sith to readily kill his hunters.
On the hunt's fourth day, Tarkin orchestrated an operation aimed at stealing the lightsaber. The hunters located Vader near a cliff, where he launched an assault. After the Sith Lord ran a fellow hunter through, Eighty-One deployed its cable to ensnare Vader's lightsaber, pulling it away while simultaneously firing at the Sith Lord. Eighty-One and the other hunters then unleashed a barrage of fire upon Vader. However, the Sith utilized his Force powers to snap the neck of one hunter, compelling the others to retreat. Vader then used a Force choke on another before the remaining hunters managed to escape.
As Tarkin anticipated the dawn of the ninth day, Vader was observed donning the hide of a Valath. Tarkin announced to his hunters that it was time to advance, instructing Gil and Eighty-One to take the lead. The group embarked on a search for Vader, entering a crystal ravine. Eventually, the Chadra-Fan Hardhear detected Vader's breathing. Due to the echoing effect of the crystal walls, they could not track Vader with their hearing because of the echoing of his breathing. Tarkin commanded the hunters to flee, with Eighty-One covering the rear as they began to move. Vader then launched an attack, hurling Gil against the wall and Force-choking Hardhear. Subsequently, he leaped from the ravine's edge directly onto Eighty-One, instantly destroying the droid.
Eighty-One was armed with a blaster and possessed a cable on its right arm, enabling it to seize objects from a distance.
Eighty-One's initial appearance occurred in the canon comic Darth Vader (2017) 18. Charles Soule wrote it, Giuseppe Camuncoli provided the illustrations, and it was released on July 11, 2018.