During the Daesong period, Seo-nyeong, who was working as a bridgehead for the Geumchang class, paid sick leave and helped Yangsan-bak to repel the subjugation of the royal court. The court ordered Ho Yeon-jak to subdue Yang Yang-bak, but he was puzzled by the news that Ho Yeon-jak was defeated. Wang Tae-wi, who learns that Pain was in the Seonyeong family's festival, the Gugyeom Changbeop, uses this as an excuse to plot a scheme to steal Seonyeong's secret weapon, the Bogap, which cannot penetrate even spears and arrows under any circumstances.