An expert in mine survival, Thur joined the Galactic Outdoor Survival School's training program for that specialization, and was a member of the prestigious Twilight Class. Once the Twilight Class graduated with honors around 10 BBY, GOSS's dean Barosa Warren offered Thur a job as instructor at his School, and Thur accepted.
However, soon afterward, the rest of the Twilight Class joined the Rebel Alliance. Thur decided to leave his job at GOSS and follow his classmates.
As a member of the Rebel Alliance, Thur survived in some of the most dangerous mines known. He even escaped the infamous Spice Mines of Kessel, rescuing in the process a fellow Rebel called Thar'quan - although not before a mine accident that paralyzed the right side of Thar'quan's face.