The Serpent Masters, a band of scavengers operating on Ophideraan during the Galactic Civil War, were under the leadership of Tyrann, also known as the Supreme Serpent Master. Housed within the Great Well, these scavengers were known for their typical attire of recovered stormtrooper armor and their armament of power lances which discharged disrupter rays.
Their designation, Serpent Masters, stemmed from their ability to manage the flying serpents indigenous to Ophideraan; these creatures demonstrated responsiveness to particular ultrasonic frequencies and pulsations. Tyrann utilized a transmitter embedded in his medallion to broadcast specific signals to the serpents, thereby exercising control over their actions.
Within the Great Well, the Serpent Masters managed a slave labor enterprise, directing a workforce that extracted water from the sinkhole's depths, while the Serpent Masters themselves resided in the elevated sections. Furthermore, they conducted a salvage operation, exploring the planet in search of wrecked starships, technologies, and droids for retrieval to the Great Well. Tyrann enlisted Tanith Shire to configure droid barges originating from Fondor to intentionally crash on Ophideraan, subsequently becoming salvage material for the enslaved laborers.
Upon Tanith's accidental crash landing on the planet alongside Luke Skywalker, the Serpent Masters transported them to the Great Well, assigning them duties within the Slave level. However, Skywalker's droid companion, R2-D2, successfully replicated the Serpent Masters' command signal, granting Luke command over a serpent. Utilizing this control, he ascended to the upper echelons, destroyed Tyrann's medallion—leading to the Supreme Master's demise—and thereby nullified the Serpent Masters' dominion over the serpents. Subsequently, the slaves assumed control of the Great Well's operations.