Lun Rask, a Black Sun vigo affiliated with the Houk species, held sway over the Arkanis sector around 137 ABY. He established his stronghold and operational center on the gas giant Kaer within the Siskeen system, repurposing an old tibanna mining platform for his purposes.
When Rask received word that his subordinates were being captured or killed while attempting to pilfer goods from Imperial vessels, he became determined to uncover the identity of the one responsible for these thefts. He confronted his information dealer, Naxy Screeger, at his base, threatening to remove Naxy's lungs unless he revealed the pirates' identities. Unbeknownst to Rask, Naxy was in direct communication with Cade Skywalker, who was, in fact, behind the robberies. Naxy soon made his escape, and Rask killed the alien who had been watching over him.
Following Cade's meeting with Muz, a Fence, on Tatooine, Muz informed Rask of their encounter, but provided Rask with the alias Cade had given him: Luke Skywalker. Rask still kept his word to reward Muz, and commented that it was the reason he would not kill Muz this time.
After Gunn Yage received orders from her mother, Nyna Calixte, to go to Tatooine and assist Morrigan Corde, she was briefed by Moff Nieve Gromia about who was truly responsible for the attacks. Yage corrected Gromia, stating that the real culprit was Cade, not Luke. Shortly after their meeting, Gromia returned to her private quarters and contacted Lun Rask. Together, they devised a plan to assassinate Cade and Gunn on Tatooine, with Rask providing three assassins: Ku Vrat, a Blood Carver, and Sint and Nakia Yoru, an Anzati couple.
However, Skywalker and Yage successfully defeated all three assassins, took Nakia Yoru as a prisoner, and met up with Agent Corde. Yoru agreed to guide Corde, Skywalker, and Jariah Syn to Rask's base of operations. Once there, Skywalker forced Yoru to cooperate by holding him at lightsaber point, and suggested they work together to steal from Rask's fellow Vigos and potentially eliminate them. Rask accepted Cade's proposition, but Agent Corde decided to shoot the Houk regardless. She justified her actions by claiming that Rask was being dishonest and would not have allowed Cade to leave the station alive.