Elixir of Life

Elixir of Life is a product of the Sacred Flame, utilised by the Sisterhood of Karn to give them extended life.

It can also be used to restore a person/Time Lord after a dangerous battle. (DW: The Brain of Morbius)

It is formed as water from underground springs pass through the rocks heated by the Sacred Flame directly below them. The rocks contain numerous rare minerals and compound which are released into the water when heated.

It is most likely a key ingredient in Sisterhood Salve.

It is produced on Karn via the Sacred Flame and the rocks in which the flame is housed, a goblet is placed below the flame producing the Elixir. This may be a remanent of the Pythia's 'magic'.