Xie Qingxue needed Zheng Fa to keep a secret for her.
Zheng Fa, on the other hand, was very tempted by the Qingping Sword—
Just as Xie Qingxue said, even without considering the trouble from the Tianhe Sect, the threats from Leiyin Temple and the Great Freedom Demon Ancestor could not be ignored for the Xuanwei Realm.
Yet, others believed that Zheng Fa would choose to ally with one of the five sects of the Xuanwei, but he still harbored thoughts of independence:
To be independent naturally requires strength.
Why wouldn't Xie Qingxue and the Qingping Sword, who came to him on their own, count as Xuanwei Realm's own power?
Moreover, for Zheng Fa, if anyone in the future claims that the "Jiushan Golden Core Method" is not original... Xie Qingxue will make sure they meet their end!
...
Xie Qingxue's addition to the Xuanwei Realm was obviously beneficial—just as Yan Wushuang thought, her understanding of the "Nine Reincarnation Golden Core Method" is unmatched by Yan Wushuang.