[The audio feed opens, but remains quiet a moment, save for the clack of a buckle being fastened. When the Doctor speaks, it's with a gravity one might expect in a eulogy.]
Truth, as observed by Lord Byron, is stranger than fiction. Reality itself, for example. In the reality I hail from alone, there are billions of dimensions, seen as separate realities, if not universes within one. Most dimensions contain catalysts to bear others, which hold foundational dimensions even within themselves, rendering them independent. I believe a close approximation, in Earth terms, may be an offshoot of fractal cosmology. A popular theory is that these dimensions are derived from the choices we make, created by the options we didn't employ. That's... true, on occasion. But in the grand scheme of things, surprisingly infrequent. Many are anomalies, split from their parent reality by a force as simple as a thunderstorm, or as complicated as Time. For all any of you know, you may be a fragment of my reality, or vice versa. I've never been one to shun possibilities.
[Zip.]
A time rift, as some of me may know, is something akin to a storm, or perhaps a temporal current, that happens to be a destructive force of its own. They're often attracted to fixed events in a timeline, particularly because they seldom cause damage to those. Fragments, however, are sometimes stripped away, to become dimensions of their own, far removed from the parent. This is as much a fact as the air most of you require to survive. As much as I don't want to be, I am a fact, directly alongside the self I'm derived from. My dimension, however, is strewn with entropy--marred and shredded by the rift that expelled it. While I've been told often enough that I'm not to blame for that particular branch, it is my responsibility.
[Sigh.]
Death is permanent, and the laws of Time hold. If I've found a way to save them, then I must. The schematic and formulae... I've got to. I don't know if I'll return, but it isn't fair to pretend certainty, nor to expect anyone to wait. I've made my preparations.
[Warden Filter]
Whichever of you receives authority to look after Coyolxauhqui, I wish you the best of luck, and I'm confident in your abilities... all of you. Remember, please, that a deity isn't an animal, or some sort of hoodlum. Revere her, understand her, help her to understand you, and I know that you can earn her trust. Seek ways to show her how the error in her ways are relevant to herself and her people. There are a great many volumes in the library that will tell you exactly why she is the way she is, and I'm sure they'll be just as helpful as her file.
[Private: Admiral]
Please restore Coyolxauhqui's access to private and filtered entries, as well as the decks she would normally have access to. Revoke my restriction against her forays to the Enclosure so that any warden may allow her in again. And... look after yourself, old chap.
--
Nothing is pointless... even here. I maintain my faith in every single one of you, whether I've met you or not. And those I have... I shall miss you, whether we remember each other or not.
[With that, he deactivates the communicator one last time, leaving it on his desk, and seconds later, the grind of the TARDIS engine echoes through his corridor. At least this time, there are no explosions.]