Yin Jiao is the elder son of King Zhou and Queen Jiang in Investiture of the Gods. After Daji engineers his mother’s death and the princes are marked for execution, Guangchengzi rescues Yin Jiao and trains him at Peach-Source Cave on Mount Nine Immortals. He descends transformed into an indigo-faced warrior with vermilion hair, fangs, three heads, six arms, and an extra eye—far removed from an ordinary court prince.
Guangchengzi gives him a fangtian halberd, the Fantian Seal, the Soul-Falling Bell, and Male-and-Female Swords, requiring an oath that betrayal will bring death beneath the plough. Yin Jiao should aid Zhou, but Shen Gongbao exploits his grief after Yin Hong is reduced to ash. He changes sides. The seal knocks Nezha from the Wind-Fire Wheels, while the bell throws Huang Tianhua from the Jade Qilin and Huang Feihu from the Five-Colored Divine Ox, proving his threat through visible defeats.
The Chan immortals finally block every escape with sacred banners and neutralize the seal. Yin Jiao then suffers the punishment he named, cut down under the plough for breaking his vow. At the investiture he becomes the Year-Guarding Tai Sui, charged with the year’s fortune and misfortune. His royal origin, monstrous battle form, halberd, multiple treasures, and self-pronounced end make his story a tragedy of filial grief turned into rebellion against his own teacher.
