For a Pharmacist, the most difficult thing to refine isn't Body Ointment, and it's certainly not Longevity Medicine. It's the Life Pill. The requirements for creating a Life Pill are simply too demanding. A Pharmacist's Power, their Fire Control—both must be at an incredibly high level. Whether it's the alchemy techniques, the Fire Control, or even the pill retrieval methods... a single mistake in any step can easily ruin the entire batch.
Furthermore, a single cauldron of ingredients can only produce one Life Pill, yet Life Pills are the most in-demand of all elixirs. After all, not every Cultivator needs Body Ointment, and not every Cultivator needs Longevity Medicine, but every single Cultivator can benefit from a Life Pill! For this reason, Life Pills are often more sought-after than even Longevity Medicines.
