Niu Mowang, localized as King Gruesome in the English adaptation, rules the Flaming Mountains alongside his wife Princess Iron Fan, known as Queen Gruesome. This minotaur-like bull demon commands demonic forces from his volcanic domain, distinguished by his prominent horns. Seeking to extend his lifespan by consuming the monk Sanzo (renamed Prince Amat), King Gruesome dispatches the imp Shoryu to lure the pilgrimage group into his territory. He actively obstructs the protagonists by triggering volcanic eruptions to block their path across the mountains. His wife possesses the critical Basho-Sen, a magical fan capable of freezing lava flows. After the protagonists fail to steal the fan using deception, King Gruesome captures Sanzo/Amat and Zhu Bajie (renamed Sir Quigley Broken Bottom), preparing to cook them for a demonic feast. During the final confrontation, he betrays his subordinate Shoryu by imprisoning him. Sun Wukong (localized as Alakazam) and Zhu Bajie intervene, freeing Shoryu and the captives. In the ensuing battle, Zhu Bajie freezes Princess Iron Fan while Sun Wukong defeats King Gruesome, causing him to fall into lava. Zhu Bajie then uses the Basho-Sen to solidify the lava, ending the threat.