databank
900 year diary
enlightenment crystal
Apparently little more than a glowing jewel located within the crystalline citadel of the Enlighteners, floating in space. The Enlighteners were the Black and White Guardians and the Enlightenment Crystal was nothing more than a physical object which signified that its owner possessed enough power to rule the Universe. The Eternals were racing to win it, but Turlough was the ultimate recipient of the crystal. However, realising that to take it would be a betrayal of everything the Doctor fought for, he rejected it and thus broke his bond with the Black Guardian. With the Black Guardian's revenge again thwarted, Turlough rejoined the TARDIS crew, this time as the Doctor's friend.