Yun-Yammka, known as the Slayer, functioned as the war deity for the Yuuzhan Vong. The warrior caste offered their worship to Yun-Yammka, and he instructed the Yuuzhan Vong on the significance of blood sacrifices. Every supplication made to him involved a death sacrifice, with the exception of the morning and evening prayers.
Each and every Warmaster was reshaped to resemble him. However, in artistic depictions like statues, his physical form mirrored that of a yammosk. The warriors displayed a fervent dedication to him, with certain warriors even prioritizing him over Yun-Yuuzhan in terms of significance. Within the context of Yuuzhan Vong religion, Yun-Yammka frequently appeared alongside Yun-Harla as the Twin Gods.
Although Yun-Yammka held a position of importance in Yuuzhan Vong culture, he wasn't originally one of their gods. The priest caste brought him into existence when the Yuuzhan Vong transitioned into a more aggressive, war-driven society. The Order of Yun-Yammka served him.
Yun-Yammka also held the position of patron for prefects. Certain philosophers held the belief that, on occasion, he acted in opposition to the Yuuzhan Vong's interests.
Onimi was under the impression that the essence of Yun-Yammka resided within Luke Skywalker.
The Festival of the Twin Gods, a Yuuzhan Vong holiday, served as a time to celebrate and pay tribute to Yun-Yammka and his sister, Yun-Harla.