Tan Yuster, a human, served as the Padawan to the Zabrak Jedi Master Agen Kolar. These two were part of the Jedi assault team that went with Mace Windu on the mission to Geonosis, an event that marked the beginning of the Clone Wars in 22 BBY. Yuster met his death during a battle in the Geonosian Petranaki Arena, overwhelmed by numerous B2-series super battle droids. As a sign of respect, Kolar recovered his fallen apprentice's lightsaber, keeping its kyber crystal and incorporating it into his own weapon. Following the conflict, Padawan Iskat Akaris contemplated the losses suffered by the Jedi Order, noting the absence of Yuster, Lumas, and Galdos Stouff.
Yuster carried a lightsaber with a blue blade and was dressed in traditional Jedi robes.