C563 Qin Jingshi's Plan
Yuen Chengji's question cut deep, and for good reason.
Changing a pill formula isn't something done lightly. Without decades, perhaps even centuries, of experience in pill refining, altering a formula would be unthinkable.
Clearly, the Blood Spirit Pill didn't originate from the White Crane Peak Pill Academy, which leaves only Yu Kun as the possible source