Jing Tianming, Ge Nie, and their companions manage to escape Wei Zhuang's assassins and take shelter within the Mohist School's hidden fortress, Mechanical City, which is tucked away deep in the mountains. This heavily guarded stronghold, defended by complex traps and mechanical creatures, remains one of the few locations beyond the reach of the Qin Empire, serving as a sanctuary for those resisting its rule. Even though breaking into such a secure place is difficult, Wei Zhuang secures the help of the formidable Gongshu clan, renowned for their aggressive and war-focused mechanical creations. Equipped with their deadly devices, Wei Zhuang dispatches a specialized unit into Mechanical City to create chaos and tear the fortress apart from the inside.