Qiyan suffered a major defeat in the duel of magic, losing two of its Kalpa Passing Stage Masters, Ji Chen and Ji Xin.
Qingqian exhausted its resources, with Chong Yuxiao and Yan Monarch falling under Lu Bei's hand. The wealth accumulated over a thousand years was almost wiped out. Among the figures who were previously at the level of the Nine Sword Elders, only Wu Chengyi and Jun Fei managed to escape.
Moreover, without the Nine Swords to aid them, these two couldn't stand out among the Integration Period. Let alone competing against Lu Bei, they couldn't necessarily win against Wang Yan either.
Zhu Mu believed that Qiyan's silence was an implicit admission of defeat, and it was a good time to invade Qiyan's territory and expand Wuzhou Country's borders, thus publicizing the might of Wuzhou Country.
Qiyan initiated the provocation first, hence Wuzhou occupying its territory was justifiable. No one could find fault in this.