An
elixir which was saught by
alchemists in the past.
The elixir would either bring immortality, cure disease, or bring one back to youth.
One example of such an elixir:
Po-Yang's:
Gold fluid is
cooked for thirty days, and then mixed with
quicksilver and placed in a yellow
jar, which is then sealed with
mud and
heated for sixty hours. The resulting "
medicine" will give the taker
immortal powers.