Undlar was a member of the Pevvni Purists, a group that opposed the control of the artificial intelligence Ganitriul over much of the society of planet Eerlik. Sometime in late 2375 or early 2376, he infiltrated the Eerlikka priesthood, who were responsible for the supercomputer's maintenance. During his first month in this position, was able to use his computer programming skills to introduce an invasive and debilitating program into Ganitriul, as well as posting other Purists at Ganitriul's moon-based facility.
Upon Ganitirul's initial failure, Reger Undlar took advantage of the chaos to assassinate the rest of the clergy. When he was discovered by First Speaker Ansed, he claimed they had been attacked by unknown assailants, and Ansed took him with her to Valandriw Hall to meet with the other assembled Speakers. There, Undlar revealed the existence of a Pevvni ship that would be capable of operating even without Ganitriul's assistance. When Ansed decided to hire this ship, the Senbolma, to take her to Ganitriul's moonbase, Undlar secretly boarded with her, and killed her.