The Twin Wu-Hook Swords are Mu Zha’s paired sword treasures in Investiture of the Gods. Carried on his back, they can leave the bearer and act in the air, giving his swordsmanship a distinctly immortal character.
Chapter 39 directly names the two swords Wu Gou and distinguishes a male and a female blade. Mu Zha shakes his shoulder and sends the male sword into the air against Li Xingba. This is an explicit narrated action, not merely a later decorative convention.
The pair makes Mu Zha recognizable beside his differently equipped brothers. Wu-Hook retains the Chinese weapon name, while the chapter’s description as swords leaves no need to impose a modern martial-arts hook-sword design.
