Rance Lussk was a student of the dark side, specifically a Sith Acolyte, who pursued his studies at the Sith academy that was located on the planet Odacer-Faustin.
As the most skilled student within the academy, Lussk dedicated the majority of his time to individualized training sessions. These sessions were conducted either with Shak'Weth, the Sith Blademaster, or with other esteemed Masters of the academy. Throughout his time at the academy, Lussk engaged in duels against numerous students. As a result of their defeats against him, three of these opponents chose to leave the academy, while one tragically killed himself. In the year 3645 BBY, Lussk issued a challenge to a fellow student, Wim Nickter, which Nickter accepted. During their confrontation, Lussk employed the Force to manipulate Nickter's movements, ultimately disarming him, but choosing to spare his life.
Subsequently, Lussk faced a challenge to a lightsaber duel on the academy grounds from another student, Mnah Ra'at. During the brief duel, Lussk and Ra'at witnessed Nickter and another Sith student, Jura Ostrogoth, plummet from the uppermost window of Darth Scabrous' tower, seemingly to their deaths. When Nickter regained his footing and began running towards them in a crazed manner, Lussk pushed Ra'at to the ground, offering him as a target for Nickter, and then fled the scene.
Later that evening, Lussk found himself in the dining hall, which had been locked down by the Sith Masters in an attempt to contain the crisis of students returning from the dead. He was present when a group of undead students entered the cafeteria, initiating an attack that led to the infection of living students. Lussk utilized his advanced abilities to fend off the infected students, but he also sensed the power that the Sickness bestowed upon the undead, and he desired it for himself. Consequently, Lussk made the decision to slit his wrists and deliberately allow the undead students to infect him.
Initially, Lussk was impressed by the enhanced power and strength granted by the Sickness. However, he soon realized that the infection possessed its own will and sought to completely dominate him. Despite Lussk's attempts to resist, he was unable to overcome the Sickness's power and ultimately joined his fellow students as an undead husk.
In his undead state, Lussk later managed to board the ship, the Mirocaw, belonging to the bounty hunter Tulkh. After the ship had departed with Tulkh, Jedi Hestizo Trace, and mechanic Pergus Frode on board, Lussk revealed himself in Tulkh's trophy room, launching an attack on Trace, who remained uninfected. Trace successfully evaded Lussk's attack, throwing him into Tulkh, who was also infected. Trace then opened the Mirocaw's airlock, ejecting Lussk, Tulkh, and the contents of the trophy room into the vacuum of space.
Lussk had significant Sith potential, making him a formidable opponent that few students at the academy were prepared to face in a duel. He demonstrated proficiency in both the second and fourth forms of lightsaber combat.