Pill of Estrangement. It had very mysterious properties, and if it weren't for the fact that the cultivation world encouraged competition and eternal development, it would have been banned.
It allowed, upon use, to expel the soul. Of course, it was mainly used by people who had been influenced by some spirits.
However, it was more often used in evil rituals. In addition to the fact that the origin of the pill is quite questionable, it is difficult to prepare, and the ingredients are extremely expensive.
Nevertheless, the demand for this pill is high. After all, most cultivators who love to roam around abandoned graveyards or Cultivator Tombs often get infected with an alien soul.
And so, in response to the question about the price, Wan Feifei gave a rather simple, but confident answer: