On the day that the boy who calls himself Theta Sigma is inducted into the Academy, he learns three true things that he will come to think of as more important than anything else he learned in his time there.
(-he approves. "Now return to your school, my boy. You have much to learn. Return to-)
'Why thirteen?' Koschei wonders, sitting across from him on the grass, and Theta looks up from his scribblings, squinting in the sunslight.
Koschei's been perusing a book, the massive tome open on his lap, and only then does does it register with Theta that it's probably forbidden. Actual, physical books are hardly the norm, after all, and the only reason any information is likely to be kept in one is either because the book itself is ancient, or the information it contains considered 'unsuitable' for digital storage. Or both. Unsuitable, of course, means it's either dangerous or that it diverges from the progression of history as the Time Lords determine it ought to be, and Theta Sigma and Koschei are drawn to both of those like the proverbial moths to the flame. Koschei frowns at the book thoughtfully.
'Regenerations,' he says after a moment, and it takes Theta a short delay to realise that he's answering his question. 'Why thirteen?' he repeats, looking up at Theta, who shrugs.
'You know why; the genetic print becomes unstable after thirteen. The... risk of mutation or mental deficiency becomes too great after the thirteenth body-' the words have the halting monotone of a passage memorised from a book, and Koschei sneers.
'Yes, I know that, but why? They never properly explain it, just expect us to settle for the status quo and leave it at that. There is no solid scientific reason why it should be impossible for a stable, intelligent Time Lord to regenerate fourteen, twenty, fifty times if he wanted to.'
Theta finds himself vaguely disturbed by this, and he sets his notes down to give Koschei his full attention. He nods at the book. 'And what brought this to mind?'
The book, as he expected, is certainly ancient, the pages, when Koschei turns it so Theta can see, are marked with the circling whorls and neat gridlines of Old High Gallifreyan, and he peers at the leaf nearest him. He positively boggles halfway through the second sequence, darting an accusatory, admiring look to Koschei. 'It's not-'
'It is,' he smirks. 'A record, kept by Vandekirian, as he assisted Rassilon in his researches. He narrates his processes at some length- apparently Rassilon had tried, and failed, several times, to come up with a method of rejuvenating the body, to extend life- there's some rather horrific stuff in here, actually, mutated corpses and the like- before he came up with the idea of reconstructing the Gallifreyan genetic code with a series of self-replicating biogenic molecules.'
Some of this Theta Sigma has heard before, and some of it he hasn't, but it's clear Koschei hasn't got to his point yet. He gives him an unimpressed look. Koschei knows what the look means- they know each other well enough that words are hardly required for such things, and continues. 'So he lights upon the idea, tests it, makes sure that it works, and puts the limit on thirteen. But no real reason why. No scientific proof, no records of tests, merely an arbitrarily chosen number, which we accept because it was the great Lord Rassilon who came up with it.'
'So what are you proposing; we change that?'
It is slightly disturbing, what he thinks Koschei's proposing, but Theta is intrigued nonetheless, his scientific interest piqued. He and Koschei have embarked on such experiments before, though always hampered by the measurements of their shared room, the only place where it's really possible to keep things like that secret.
Koschei shrugs. 'Maybe.'
'I was only thinking,' Koschei says dismissively, and returns to perusing the book with that little frown creasing the space between his eyebrows. Theta watches him for a moment or two, three, four, before returning to his own notes, picking them up from the grass and brushing off a small, curious green insect which had been occupying itself trundling across disorganised quasitronics expressions.
(He wants nothing more than to lie down and sleep)
He's huddled against the wall in a wretched prison cell in Atlantis, and next to him, Jo is miserable with cold and fear. This regeneration isn't particularly good at comforting, it doesn't come naturally as it did in the body before this one, but Jo is clearly in need of it, so the Doctor casts his mind around, and he's quietly pleased to himself at what comes to mind. So he tells her the story of the day he was initiated into the Academy- the hermit on a hill behind his house, and the daisiest daisy he'd ever seen, and as he'd hoped, she's comforted by it. She even manages a smile, when he asks her if she's still frightened.
'Not as much as I was,' she says a bit shakily, and the Doctor smiles too. Good.
Later, with a dead man lying across the cell from them, Jo has curled up against him, face buried in his shoulder, having fallen asleep, exhausted from fear and sorrow over poor King Dalios. The Doctor had once said to Victoria that memories slept in the back of the mind, that one had to really want to remember them to wake them up and bring them to light. Now that he's brought up the memory of his initiation day, it doesn't seem to want to go back to sleep. It's too easy, sitting here in the dark, to remember the strange walls of the Prydonian dormitories, Jo's body small and warm and in need of comfort too much like eight year old Koschei's. Koschei, the Master, who even now is upstairs in the Queen's bed, with chains ready for the Doctor in the morning.
Sighing, he closes his eyes against the darkness, and tries to fall asleep. He doesn't really expect to be able to, and he's not disappointed.
It's the first time he tells that story, but it's not the last. Hopeless situations, after all, are nothing rare as far as the Doctor's concerned, and so the story of the daisiest daisy gets told to Sarah Jane, to Tegan and Nyssa, Peri and Erimem, to Ace and Charley and C'rizz. C'rizz asks what a daisy is, and Charley hushes him and tells him that that isn't the point. And over the years, the story changes, parts of it left out until those memories never wake up at all, gathering dust in the back of his mind so that the Doctor almost forgets them himself.
Not that it matters, not really; it's still the brightest day of his young life, and if he chooses to forget some of the reasons why, their effects are still there, even so.
(Nothing matters, because the only thing that will last-)
The Master rises, cackling, like some kind of twisted Lazarus, and the cool, underwater light of the numismaton gas washes about the chamber. His features are obscured by the blue flame, but his fingers flex at his sides, his head tilted back- the Doctor can practically feel his pleasure, both at being restored to himself finally, and at a plan gone well.
Flawless, for once.
Except for not, not quite, and the Doctor can see it just before it happens. The flames are red against the back of his eyelids, and it's no surprise when he opens his eyes to a shriek from the Master.
He's burning, and though the Doctor expects it, had seen it there, for an instant, a sudden surety in the constant spinning, branching threads of what could be, still he freezes, eyes wide. Everything dies. Eventually, everyone dies, the flames and supernovae of death giving way to nothing but vast blackness. No exceptions. Except for the Master- he fought, fights, pushing himself beyond all tested limits, refusing to accept that one simple, inevitable fact. The Doctor doesn't like it, but he understands.
The Master had never understood that.
And maybe, just maybe, if the Doctor lets him die here, on Sarn, in the heart of a volcano, he'll realise. He doesn't have to fight for some hideously distended lifespan, because even as everything dies, everything lives, there is no one without the other, and the life that death makes possible is beautiful.
'Help me! I'll give you anything in creation! Please!'
No, no, no, he doesn't understand! The Doctor isn't doing it for himself, he's doing it for the Master. For Koschei. No more regenerations, he'll be dead for good and all, he'll stop fighting then, maybe-
But he can't do it. The Master is holding out his hand to the Doctor, a plea, for once, instead of an offer, and standing there, paralysed, the Doctor hates him for it. He barely makes the decision consciously, his hand moving of its own accord to flip the switch that cuts off the stream of volcanic gas, and then seizing the Master's, pulling him out, away from his TARDIS and the vent in the floor, into the main body of the cavern. Because the Master has never really understood life either, and there's no way for him to learn that if he's dead.
The velvet of his suit is scorched now, his perfectly combed hair a mess, and what skin the Doctor can see looks tight, pink and painful from the heat, but he's alive. Alive, and when the Doctor looks at him, it's as if he can see him growing still, every cell in that stolen Trakenite body rejuvenating, healthy and strong. He refuses to allow himself to think that anything but a good thing.
'Everything dies,' he insists, wide-eyed and angry. 'Everything, Master.'
But the Master merely shakes his head, chuckling, and extracts his hand from the Doctor's vise-like grip. Blank, the Doctor looks down at his hand; he hasn't realised he'd still been holding on.. 'Not everything, my dear,' the Master corrects him lightly, all dignified leering once again, collected, as if he hadn't nearly burnt to ashes.
Does he realise, the Doctor wonders, how very close he'd been to letting him die? He doesn't know, just continues to stare at his hand. 'I have to find Turlough,' he mutters after a moment, and looks up to hold the Master's eyes for one, horribly long moment, before turning and positively fleeing into his TARDIS.
Once the echoing grind of dematerialisation has faded, the Master shakes his head again, eyes narrowed and expression shrewd. The Doctor has no idea, does he?
("Oh," the boy murmurs. "Oh. I see." Then he laughs.)
On the day the boy who calls himself Koschei is inducted into the Academy, he sees the future. A million million potential futures laid out before them, things that might be and things that might never, and laid over them all are flames and entropy and echoing back from one of those far, far futures, the sound of drums. He stares, the swirling chaos of it threatening to overwhelm him, terrifying, rooting him to the spot, huge where he is nothing; he's drowning in it, but he resists fighting gamely with all the power he has in his small body and mind, and eventually, it recedes, and Koschei blinks spots away from his eyes. He finds himself trembling, but the approving hand of one of the Attendants comes to rest on his shoulder and tells him that he had done well.
He walks, or so he imagines, as he's guided to walk, and answers with the correct words to any adult who addresses him, but he can't really pay attention to any of it. He doesn't really feel entirely there, somehow, and when he lays down on his new bed in his new room, he hardly notices that he's crying until another boy slips onto the bed next to him. His name is Theta, he says, and Koschei realises in that same small, distant way, that he recognises him from those futures he'd seen.
Well, that's alright, then, and he nods tightly as Theta takes his hand.