In this chapter, the master of poisons explains how he can use his secret weapon to increase his combat power. He explains that he has made a powerful sleeping potion, called "soul fragrance," which causes a person to be comatose for ten hours and then lose short-term memories. He has also made a "enhanced version" of the same potion, which causes the person to lose their memory for a short period of time. The master explains that in order to become an "all-around poison-immune" person, one must cultivate the habit of taking small doses of the deadly poison every day. This way, the poison will kill two birds in one stone.