Yanyan was hardly unfamiliar with the Sealing Sleep Curse; it was one of the forbidden arts of the Yin-Yang School, specifically one of the Eight Yang Curses, making it the exact counterpart to the Six Souls Fear Curse—one of the Eight Yin Curses—that he had previously contracted.
He had even gone so far as to consult top-tier experts like Yan Ao and Wuming regarding the eight major forbidden arts of the Yin-Yang School.
The answers he received, however, were somewhat unexpected.
Chapter 172