The Yun-Yammka Battle Group served as one of the five battle groups that were part of the Yuuzhan Vong forces in the Battle of Ebaq 9.
Upon the Yuuzhan Vong's arrival at Ebaq 9, Warmaster Tsavong Lah gave the order for the Battle Group to engage the squadron led by General Keyan Farlander. As the tide of battle turned against the Yuuzhan Vong, Lah chose to sacrifice the Battle Group, facilitating the escape of the remaining fleet. No member of the Battle Group voiced any opposition. When Lah commanded the retreat of the rest of the forces, the Yun-Yammka Battle Group remained too deep within the Treskov system's gravity well to successfully retreat, resulting in the destruction of every single ship.