He closes his eyes as he pushes the button to lower the helmet for the Chameleon Arch down. Looking up at it, it seems so innocuous, really just four prongs with a space for the watch and his head. But it's so much more. It can change him, it can rewrite his biology, and it can make him forget everything that he's lost.
He looks between the Arch and the console before looking back up at it. He's made his choice, and maybe now he'll finally be able to find some peace.
He walks around the console to the video screen telling the Tardis to play over each of the videos one last time. It wouldn't do for the wrong instructions to make it into the wrong video. There is one for his companions in case the Tardis decides to take him to one of them and there is the other one for her. There is one that tells the truth and there is one that tells a lie.
He reaches down for the pocket watch that lay next to the recorder on the console. He wishes he could bring himself to smile, or to babble on about the beautiful designs on the front of the watch but he can't. He hasn't been able to in a long time.
Besides it's not like there's anyone to babble to about this, there hasn't been, not since the day the day he lost her to another universe.
With heavy arms, tired eyes, and a smile that could almost be described as peaceful he fits the watch into the indent on the side of the Chameleon Arch before stepping away. He wants to give himself one last chance to make a different choice, and to do the right thing. He almost wishes that he could, but the universe lost its one chance a long time ago. He's given it far to many chances now.
Instead he smiles, content in his decision, knowing that the hollow aching emptiness of where his hearts used to be wouldn't exist for more then a few more minutes.
With one last look around the ship that has been his home and his only constant companion he pulls the helmet down on his head. With a silent apology to his oldest friend for leaving her behind too; he signals for the Chameleon Arch to be activated.
He can feel the moment the energy begins to surge through him. It's cruel touch tearing apart his genetic code, and breaking it down replacing it with human DNA. Every cell in his body is screaming with pain as they're being torn apart and rewritten from the base code upward. He thinks he might just be screaming too, but the pain is a welcome feeling. It's one that means all of this will end soon. He knows hat no matter how much he wants to call to he won't talk. He won't break that promise to her because she deserves that much. She deserves those words to be the last words that he would ever speak as himself.
The energy careens through his body now. It's claws digging into his neurons, their axons and dendrites. It's tearing them apart, pruning away his neural connections, destroying his second heart, his respiratory bypass and everything else he won't need anymore. He welcomes it, the feeling of the worsening pain and the uncontrollable spasms in his muscles. He welcomes the feeling of being torn apart from the inside out, and put back together in a way that feels wrong, but oh so right, because he's starting to fade. He's starting to be channelled into the eternal sleep that being trapped inside the watch will bring.
He wants to laugh in triumph.
It's almost the end of him. It's almost the end of the Doctor. It's almost the end of the man who destroys everything he touches.
He welcomes it.
He revels in it because it means that this accursed life will be over soon. Unless of course someone manages to find the watch and open it, setting him free. That won't happen though because he didn't leave instructions to open the watch in his video to anyone who enters the Tardis.
He won't be brought back into this accursed world and ungrateful universe not unless she does the impossible yet again and comes back to him.
He can feel it now as he begins to fade away, dragged towards the edges of slumber. The new consciousness exerting itself as the false memories are placed in his head. It feels strangely familiar somehow, almost like a forgotten dream or a life never lived. He can't bring himself to care, not really, because it's finally happening. He's finally fading, and he's not scared; he's just tired.
He's so tired, but ever the babbling fool he can't help but shout triumphantly for felling the universe this once.
Finally! he laughs in his mind as everything finally fades away because he finally won and the universe lost.