Tamlen was a male Human Sith Acolyte of the male persuasion, affiliated with the Sith Empire during the era of the Jedi Civil War.
As a Force-sensitive Human, Tamlen's education in the ways of the dark side of the Force was provided by the Sith Empire. In 3956 BBY, he underwent training at the Sith Academy on Korriban, mentored by the masters there. While a student, Tamlen's duties involved updating the library's records with new information, including the history of Ajunta Pall. His studies of Pall led him to a legend about the Sith Lord's blade. Intrigued, Tamlen shared his findings with a fellow student, unaware that he was speaking to Revan, the amnesiac Dark Lord of the Sith. Revan had been captured and brainwashed by the Jedi Order to be a weapon against the Sith.
Following Tamlen's conversation with Revan, the former Dark Lord sought out and retrieved the legendary blade from Lord Pall's tomb. Soon after, Revan, aided by the redeemed Sith Yuthura Ban, returned to the academy and assassinated the Headmaster, Uthar Wynn. Together, Revan and Ban proceeded to eliminate all Sith students who refused to embrace the Jedi path. Tamlen, loyal to the Empire, was killed alongside the other occupants of the academy.