Sisterhood of Karn
The Sisterhood of Karn was a religious order, originally from Gallifrey but since residing on the planet Karn. They protected the Sacred Flame which in turn produced the Elixir of Life, a liquid capable of extending one’s lifespan and even triggering or amending a Time Lord regeneration.
The Eighth Doctor drinks a venti of warrior juice and canonises the Big Finish adventures
Despotic Time Lord Morbius is resurrected as a Fishbowl-Claw-Monster to… take over the universe?
The Doctor and Lucie battle bionic centipedes, face the Sisterhood of Karn, and must stop the regeneration of Morbius.