When the Lin Kuei clan decided to automate their ninja in the events leading up to Ultimate Mortal Kombat 3, Sektor, out of loyalty, was their first member to volunteer to undergo the process, and would later appear to be their most successful creation yet. Designated unit LK-9T9, he was sent to hunt down the rogue clansman Sub-Zero. He attempted to complete this mission twice (during Ultimate Mortal Kombat 3 and Gold), but never succeeded. Events would leave him as the only active cyborg remaining of the three created, with Smoke having been captured and shut down in an Outworld prison, and Cyrax having become a member of the Outer World Investigation Agency after his soul was restored.
During his many violent battles against Outworld forces, Sektor's program became corrupted. He believed the Lin Kuei Grandmaster to be inferior, and set his new objective to eliminate him and took control of the clan. Sektor successfully slew the Grandmaster, but was stopped from claiming the Dragon Medallion, the proof of the clan's leadership, by a returning Sub-Zero. Sub-Zero defeated Sektor in battle and claimed the title of Grandmaster. After his defeat, Sektor fled to Japan and formed the Tekunin, his own clan of cyborg ninja warriors.
In Mortal Kombat: Armageddon's Konquest mode, Sektor ambushes Taven when the latter is in his father's temple, searching for his weapon that had been left there. He brings him back to the Tekunin warship, where Sektor began questioning Taven about the message he had received from his father, Taven warns him that he would be punished for it, and in response Sektor increases the power on Taven, bringing him pain. Suddenly, the warship is attacked by Sonya Blade and her Special Forces. Taven escapes captivity in the ensuing chaos, but Sektor confronts him and is ultimately beaten, but evidently is still able to make it off the warship alive before it self-destructs.
Sektor joins the Forces of Darkness and is killed during the final battle. His corpse can be seen on the steps of the Pyramid of Argus.