How did Zhou Yixian know that the ghost had reached the Four Scrolls of the Tomes of the Arcane?
In the fairy tale, Zhou Yixian was the abbot of the Tianyin Temple. Through observing the members of the Ghost King Sect, he found that the sect leader of the Ghost King Sect, Gui Li, had already obtained the Book of the Heavenly Book. Zhou Yixian knew the importance of this book because he knew that in the Immortal Cultivation world, only Immortal Cultivation experts could master this book. As an ordinary person, it was impossible for Gui Li to obtain this book. Zhou Yixian also knew that Gui Li had reached a bottleneck in his cultivation and needed to absorb energy from the outside world to break through. He had observed Gui Li's performance when he absorbed the evil spirit energy and discovered that there was a problem with Gui Li's energy source. Thus, he deduced that Gui Li had obtained the book, the Four Scrolls of the Heavenly Book. Thus, Zhou Yixian went to the Ghost King Sect and handed the [Four Scrolls of the Heavenly Book] to Gui Li to help him break through his bottleneck and become an immortal cultivator.