Zûk was born as a member of Dûrgrimst Az Sweldn rak Anhûin. He was not very well-known even in his clan before the attack of the Ilirean Army on Farthen Dûr in 63 Li. In this fight, he swiched sides after about a year and met Passan, Supreme Dragon Rider and therefore representative of the freedom of Alagaësia. Short after this, Passan changed sides and took Zûk with him. It was supposed that Zûk had convinced him by unknown means to team up with the dwarfs. Actually, Zûk had gathered knowledge about Passan's true name and had only changed to the Ilirean side to have an opportunity to tell it to Passan, making him his slave. So Passan started to lead Eflaim's forces against his successor Staniak. The war was going on for a longtime, but not well; and Passan wanted to capitulate, but Zûk didn't let him do so. Although his death would have been a catastrophe for the dwarfs, he participated in the fights, even killing Valgund, a high-ranking leader of the enemies' army. He and Eflaim finally had to command retreat to the Dwarven Tunnels, leaving scorched earth behind them as well as they were able to. His best friend Akar, who was engaged to his daughter Mella, commanded the defence forces, but in vain: Even here they lost ground very quickly. Zûk was eventually killed by Oroim, a dwarven dragon rider who had become friends with Passan and promised to free him. These evenements leaded to the capture and execution of Eflaim and to Akar becoming king, with his legitimacy being a friend and son-in-law to Zûk who had become extremely popular among dwarfs.