Willm Lwyin was a Jedi Knight during the time of the Old Republic over a thousand years old. A member of the Duinuogwuin, or Star Dragon, species, Willm offered a daunting presence to friend and foe alike. Having a life history that extended beyond a millennium, Willm has had much time to make a history for himself. However, little of the history is known. What is known however is that at some point in his life, Willm Lwyin became a Jedi Knight and eventually a Jedi Master. For about four hundred years, Willm traveled with and escorted a Praxeum ship, possibly the Jedi training vessel, the Chu'unthor.

Also, it is known that Willm Lwyin is the last surviving member of the founding Jedi who established the Jedi Praxeum on Teya IV, where he remained as an instructor for about six hundred years. Since the school was designed for typical inhabitants of the galaxy, Willm chose to live nearby, in the mountainous regions that held the Cave of Truth, a cave with a series of tests used as a final lesson to young Jedi Knights. Because of the incredible longevity associated with Star Dragons, Willm outlived the other founding members of the Teyan Praxeum, and was still an instructor when Jedi Master Tannis assumed the leadership of the school.

Willm took great amusement in introducing himself to young Jedi Knights and seeing their reactions to his appearance before they got to know him. Over his six hundred year tenure at the Praxeum, Willm escorted hundreds of young Knights to the Cave of Truth, most notably the young Jedi Knight Vici Ramunee.