It was mostly Ten that explained, and Donna took it all in with a odd quiet. Emily sat quietly as well, and when the story was as told as it could be for the time being, Donna looked over at the Doctor. Then at Nine, and simply shook her head.
"I knew you could regenerate, I guess it's hard to really understand until you see it."
The last time that it had happened was the beginning of some of the worst days of his life. It was what led to losing Donna.
That time he had fought it, which had been what had to happen in order to get the duplicate and ultimately win the war.
Or at least the battle.
"What did you do to her?" Emily asked after a while.
The Doctor thought of the easiest way to explain it, and decided, "We basically let her remember which burned her mind. She used the leftover energy to regenerate her body, with the TARDIS stabilizing her, and now here she is."
Emily looked at them all in turn, at least all the Doctors and finally just shook her head.
"Are you all right?" Donna and Ten asked at the same time.
For some reason that made Donna look at Ten for a long moment, before she simply shook her head as if she were clearing away a fog.
"Always," Emily muttered.
Any further discussion was cut short when the TARDIS shuttered around them. The Doctor looked up at the ceiling and felt his hearts clinch. It was time.
He didn't know where they were, or what they were facing, but outside that door was devastation. It seemed as though Donna suddenly could see because she reached out for her daughter.
The Doctor knew, with fresh memories sliding into place that Emily wasn't going to sit by idly. She was going to face this.
Ten also seemed to know this, and he stopped Donna from grabbing her. There was nothing that could stand in the way of this fate.
The Doctor led the way, and looked out on the screen. What he saw shouldn't have surprised him; it was what always came to steal from him.
His greatest enemy that would never just die, they always found a way to survive. They would survive to take from him again and again, until he feared there would be nothing left to take.
River was by his side, and she seemed hesitant. She knew they had to go out there, he doubted anyone in the room didn't know that hiding inside of the TARDIS wasn't an option.
Yet, it was a long time before anyone moved.
DOC-TOR
He heard them calling out. They seemed as surprised as a Dalek could possibly sound. They weren't expecting an opposition it was clear, and if the TARDIS hadn't brought him here, he doubted that they would have any.
DOC-TOR
Time to face the music.
He looked at the group, being reminded of that day so long ago. Back when he was Ten, back when the TARDIS was full with a different group of people. He thought it was hardly fair the only time he could have a full TARDIS was when something awful was going to happen.
Granted back then all he wanted was for everyone to leave so he could hold on to those last few moments with Donna.
He led them to the door, and opened it. The TARDIS would protect them as well as she could within her limited range. It wouldn't last long if they chose to fire, so his best bet was to keep them talking.
He could do that, and with three of him and Donna he imagined they could keep a conversation going for as long as it was needed.
When they were all out they were surrounded by Daleks. Brightly colored and newly made, similar to the ones he had seen way back when with Amy.
DOC-TOR
He heard himself, and the other two confirm at once. The closest Daleks moved back and seemed to be thinking. He could see their little gears turning, and it made him smile just a little. Three versions of the Oncoming Storm in front of them, and he was sort of pleased that he could still make them pause.
"So what are we doing here?" the Doctor finally asked, unable to bear another round of the broken sound of his name.
YOU WILL NOT STOP US
"Yes, I…we will," the Doctor told them very matter of fact.
Ten took a step forward, barely missing being stopped by both Emily and Donna at once. The Doctor could see it all so clearly then in that moment. Ten had a family, he had love, and he had to stay away from them for so long.
It made this version of him feel a little empty. He had River, he loved River, but it just wasn't like those two hands reaching out with no interest in their own lives. Only in his.
He moved past the protection of the force field, and before the other Doctor could even join him he saw Emily step out, followed by Donna.
He looked at Nine who was already moving forward. There was no choice. No one in that group was willing to leave one man standing alone.
They would all fight together.
They were their own family, which just happened to include two other version of him in it.
STOP! STAY!
They all did stop, just outside of the force field. They were unprotected and vulnerable but they were together.
"So why are we here?" Ten asked before the Doctor did.
He would have thought they would have learned by this point that getting cocky and explaining the plan to him never ended well for them. But apparently they seemed to think that this plan was infallible and they seemed eager to share.
He felt the force field go up around him, and he saw it go up around the others. No one even flinched. Not even Emily. She only reached out to touch it, watched it turn blue around her, and dropped her hand.
He thought he heard her mumble something about poor treatment of guest. Whatever it was it made Ten smile and shake his head fondly.
One Dalek moved closer to a wall and used his manipulation arm to open a lock on a wall. The Doctor watched the wall retract to reveal what looked like a lab. Inside there were workers, a variety of species- mostly the most intelligent in the universe- were working. He could see large tubes filled with a purple fluid that bubbled occasionally.
When the wall moved one of the worker looked up with a frightened expression and it made the Doctor want to reach out and help him at once. These species were only being kept alive until they were no longer needed.
He wondered if they knew.
He waited a moment, wondering if the Daleks would explain what they fluid was and what horrible thing they planned to do with it.
How were they going to destroy the universe this time?
DOC-TOR
"Yes, we've established that," Nine said with a grumble. The Doctor knew that he was nervous. Not scared, no, but nervous.
Time was running out for them, for Emily, but no one knew what the end was going to look like.
Ten, puzzled him though. He was oddly calm. Almost as if he had resigned himself to what was going to happen.
Almost like it didn't matter what they were going to lose. In reality Ten was going to pay the highest price, though they were all losing the same thing.
So why did he not look like he was worried? What did he know?
Perhaps he was just hiding it better than the others.
THIS IS THE FIN-AL-ITY VI-RUS
Well, that didn't sound good.