Celestia’s willpower fought against her exhaustion and pain, urging her to stand back on her legs. Her ribs burned, and a sharp ringing echoed in her head. She swallowed, her throat raw and sore, placed her legs below her torso and pushed. Doubt had assailed her, ripping her confidence apart, bringing down her strength. This wasn't the way it was supposed to go. There wasn't supposed to even be a resistance. She was supposed to show a minimal effort of trying to stop her and then get imprisoned. Delay her a little at best to give Twilight a little more time. Not get torn slowly apart.

She was finally up again. Her legs trembled and threatened to throw her down any second now, but she was up. She wasn't sure how much that mattered anymore.

Luna in her Nightmare Moon form stood a few meters away with an infuriating, condescending smile and watched her, her eyes illuminated by an inner fire. This wasn't like the last time. Luna wasn't like that a thousand years ago. She didn't try to punish her, to torture her, hurting her again and again, watching her strive to breathe. She didn't laugh with joy at Celestia's grimaces of pain.

Celestia glimpsed into herself and realized that this was it. There wasn't going to be another attempt to fight back. She had nothing left, no strength and no magic. Everything she could spare had gone into keeping her standing. She had lost, just like she knew she would, but not like this. Not in such a brutal, malicious way.

"Luna... Luna please. Stop this." Pleading with her was all Celestia had left. She needed to buy Twilight Sparkle time, to find friends and then find the Elements. Her student was going to need every second she could gain for her sake against this bitter, vicious Luna. With blood if she had to. She would fall on her knees and whimper on the ground begging if that meant a little more time for Twilight.

"Wrong name princess," Luna smirked, shooting off a weak beam of magic at Celestia's side, throwing her back down. "Try again."

"N-no," Celestia shouted, gritting her teeth against the pain. "You're my sister. You'll always be my sister, no matter what. Luna, please. Don't-"

Luna lifted her head up and laughed. "You might want to rethink that, princess," she said, still laughing cruelly.

Time. She needed time. If she wanted to talk, she'd talk. "What do you mean?" Celestia asked, letting her head fall on the ground, too exhausted to hold it up.

"How did it go again? "On the longest day of the thousandth year, the stars will aid in her escape, and she will bring about nighttime eternal." Yes, that seems about right. Wasn't this how the prophecy went princess?" Luna asked, heavily mocking Celestia's title every time she said it.

"Yes." Celestia didn't see the point. She was already here. Did she think that the prophecy meant that her victory was guaranteed?

"Who is her?"

"What?"

"Her. Who is her? Her escape. Come little princess. Don't tell me you missed this small detail?"

"It's... you," Celestia said, still mystified.

"And what is my name?"

"Lun-"

Luna silenced her with a hoof, surprisingly gentle. "Nuh uh uh. My name. Mine."

"Nightmare Moon," Celestia finally conceded. She was trying to make use of the time to regain some strength, vain as it was.

The dark mare in front of her wasn't done yet. "Exactly. Nightmare Moon." She lowered her head, bringing her smiling mouth, full of sharpened teeth in front of Celestia's eyes, and whispered softly, like a nighttime promise. "Nightmare Moon. Not Luna."

Celestia understood then. Dread and fear filled her, the horrifying implications becoming swiftly apparent. She tried to disbelieve it, to refuse it. This couldn't be right, this couldn't be true!

"Now you are getting it princess." The monster looked up at her sister's moon. "Poor little Luna, still stuck up there. She wasn't included in the deal you see. It's ok. I'll send her something to keep her busy. Now, should you still be breathing, or not? Decisions, decisions..."

Celestia got up on her legs again. Time. She needed to buy time, more than ever. Tears flowed down her face, blinding her while also giving her new strength. She would get her sister back. One way or the other, she was getting Luna back. She needed to buy Twilight more time. Nothing else mattered.

She charged Nightmare Moon.