Sunset stared up at her in sheer disbelief. “What?”
“I said, no! I’m not leaving you here!”
Twilight looked down at her former enemy. Then she blinked, half-shaking her head, renewing her concentration on remaining standing. One wing was again dragging the ground, twisted, worse than useless. One eye was swollen shut. Her coat was wet from a thousand small cuts, matted with bloody soot. She could feel the pain blazing in her chest again with every breath. Every suppressed cough tasted of copper.
Sunset jumped to her hooves, wings flaring. “Are you crazy?”
“Maybe we both are! But I’m not leaving you alone!”
“You have to!”
Sunset shoved the alicorn away. But instead of stumbling back, Twilight simply fell, her injured leg breaking the rest of the way with a sickening sound.
Yet, Twilight looked up at Sunset, blood trailing through her gritted teeth. “No!”
Fissures in the stony ground opened wider in several places near them, sending flames into the air. Molten lava began to spurt and bubble up around them.
Again, Sunset forced the portal open, the tear in reality’s fabric screaming in violation beside Twilight. All she had to do now was roll.
“Get out of here!” Sunset screamed.
“No!”
“I don’t want you here!”
But instead of rolling through the rift, Twilight forced herself back to her hooves. The world swam before her in a dark haze as she turned away from the portal, and towards Sunset Shimmer. Head lowered in determination, Twilight screwed her one good eye shut against the pain.
“I’m not leaving without you!”
Then, as another fit of bloody coughs forced Twilight to her knees, the mountainside behind Sunset exploded outward. Sunset had just enough time to glance over her shoulder and see an ocean of lava rising above them both.
The mirror flashed, its unearthly light again filling the chamber.
The glass rippled like water for the barest of instants before parting. Even as Celestia’s mouth passed through the portal, she was saying, “Get them medical help, immediately!” The two sisters were emerging into the crystal sanctum, the elder cradling the younger in her wings and the glow of her magic. Before them, the coronet skipped along the floor, forgotten and ignored.
But Celestia saw she needn’t have bothered speaking. Twilight’s friends were already in motion, no doubt forewarned by Pinkie Pie’s unique senses, and the sanctum was a hive of activity. Fluttershy was already at the mirror, immediately helping Celestia move Luna onto a waiting stretcher. Rarity and Applejack had taken charge, Applejack barking out basic instructions to the servants in attendance, with Rarity and Spike coordinating the details. Gently, but with professional speed, four crystal guards carried Luna away to where skilled doctors waited, the Princess of Night finally allowing herself to slip into unconsciousness.
“And you, too, Princess.”
With effort, Celestia dragged her eyes from where her sister had been taken. It was Fluttershy, of course. Soft-spoken as always, but still glaring at her sternly.
Celestia opened her mouth to refuse, but instead looked around herself, her despair evaporating into alarm and horror. “No, where’s Twilight--!”
At that instant, the mirror flashed yet again. Every pair of eyes immediately turned to the dimensional portal as it glowed and wavered. But it was not the anticipated tri-colored mane of Twilight Sparkle that parted its surface.
Rather, it was red, and gold.
The room fell silent as Sunset Shimmer stepped into the room. She was pulling something with her, enshrouded in her leathern wings. The mirror’s flash subsided, its surface rejoined again.
And then, with a terrible sound, the mirror cracked. The cracks spread out across the glass with a groan like fracturing ice. Then it burst apart, releasing flame from within itself. The flames were blinding white, and all save Celestia were forced to shield their eyes. An instant later, there was only smoke dissipating out from an empty frame.
Even as crystal ponies and the Mane Six stepped forward to deal with this new threat, Sunset opened her wings. There was Twilight, unconscious, slumped awkwardly in one yellow arm.
Celestia gasped and stepped forward, helping Fluttershy take Twilight’s unconscious form and lay her on another stretcher. Then, she looked back at her former student in tearful gratitude.
“Thank you.”
Sunset said nothing, her face stone.
Then, Celestia was helping other crystal ponies transport the soot-covered Princess of Friendship out of the sanctum, and to medical aid.
Sunset Shimmer, also covered in ash and soot, looked around at the rest of the room. She furled her dragon’s wings, meeting the ponies around her gaze for gaze, unwavering. Her voice was somewhat hoarse from smoke, but still perfectly clear.
“Well?”