Triskaidekaphobia
The deep sound of the cloister bell echoed down the TARDIS corridors for the final time. The ship was dying too, the symbiotic link had grown too strong over the millennia and the Doctor's fate was now tied irrevocably to its own.
The Doctor lay motionless on the floor of the darkened console room. Once again he had saved his friends, the world, the universe … and once again he had paid the price. This time though he knew there were no further chances at life, no possibility of recovery. This time it was different.
But he was not afraid.