His soul cultivation was only at Transcendent Mortal 9-dan at the moment. Being a soul oracle, his soul was indeed significantly stronger than most Saint realm cultivators, but it was still far too weak to be able to set up the Great Heaven Reversal Formation.
As a grade-7 pinnacle formation, it was designed with the capabilities of a Saint 4-dan Primordial Spirit realm expert in mind. While Zhang Xuan's soul possessed similar capabilities with a Primordial Spirit, it was a pity that his soul was still too weak at the moment.
Unless… he could raise the cultivation of his soul!
Of course, there was Guild Leader Han around, and there was no doubt that he did possess a sufficiently strong soul to set up the Great Heaven Reversal Formation. However, the situation was a little different here.