Jing Tianming learns more about the Mohists and the construction of the Mechanical City. Dao Zhi arrives. Emperor talks about his dream to unite the six nations under the Qin which leaves no place for the separatist Mechanical City to exist. Because normal troops could not successfully attack the Mechanical City, he plans for the Quicksand and Gongshu Clans to infiltrate and defeat Mohists. Meanwhile Master Ban explains the many traps and defense mechanisms built for defense. Ge Nie realises that Tianming has potential, but is still young and naive and will need a lot of guidance to achieve his potential. They meet teacher Xu whose mother forged Ge Nie’s sword, Rainbow Abyss. Meanwhile Wei Zhuang decides to send in Hidden Bat and Lin-er to infiltrate the Mechanical City.
进入机关城，盖聂和天明结识了墨家神偷盗跖。就在天明惊叹机关城的神奇时，碰到了前来迎接他们的墨家铸剑师徐夫子，徐夫子告诉盖聂，渊虹是自己母亲所铸。
