At the Grand Demon Assembly, Bull Demon King is mocked over doubts about Red Boy’s origin, Samadhi True Fire and the Banana Fan. Discovering Lord Taishang’s golden binding rope at home pushes him over the edge. Enraged, he grabs twin blades and storms the Southern Heavenly Gate, crushing celestial immortals. He persuades Nezha to defect and stand against Erlang God. With Sun Wukong’s help, Bull Demon King breaks into the Tushita Palace to confront Taishang Laojun. At the climax, Princess Iron Fan reveals before the Jade Emperor that she and Laojun are siblings. Bull Demon King takes the blame for his wife and is imprisoned in Flaming Mountain for 500 years, while Laojun uses this incident to cover up his missing golden pill accounts.
