The smile she gave him chittered as she attempted to walk around him; the mountain was especially cold that day, but there wasn't much need for clothing where she was going. “My special talent is power.”
He gritted his teeth, standing again in her path. “Your special talent is politics. I have been nice up to this point. If you do not turn around this instant, I will physically interrupt you—I will beat you to within an inch of your life. Don't you move a centimetre closer.”
“Politics. Social power. Focused power. Willpower.” With a flash, she enveloped the Professor in a thick pink glow; he struggled, his hooves prodding around for the spell's nexus as she stepped around him. “It's all the same. Do you know why the sky is receding, Professor?”
He prodded furiously around the insides of the web, searching for the nexus—until he realised that if he got free, the resonance from his escape would push her over the edge. He forced himself to calm down. “Of course I do; it's a natural phenomenon. What I fail to know is what you think you're doing.”
“I'm saving ponykind, Professor. The world as well, coincidentally.”
He glared at her through the pink haze. “By killing yourself?”
“Six months.” She paced gently around the rim, poking at a pebble; she kept quiet as it fell the full minute, shattering a sheet of ice. “Six months until the sky and its sun go too far for us to see. Every single one of us will starve, Professor. Not even the strongest earth pony can grow in cryotic soil. What's one to save everypony else?”
“Pony sacrifice doesn't work, Twinkle. I thought you were joking; I'm sorry that I thought of you as more intelligent than you've shown yourself to be. It's as simple as that, and I am not going to let you pursue that line of thought any more than I'm going to let you dilute your saliva in a cup and market it as an antientropic compound.”
She shook her head, the movement pushing him from side to side. “When Commander Hurricane ran Princess Platinum through five years ago during the First Internecine War, what did Platinum say as she laid dying, her horn shining?”
He sighed. “That's from a textbook. You know the answer.”
“Tell me.”
“'May the world forever be drawn from its sky, may the dawn forever flee from the earth.' The luckiest weather forecast ever made. What does that have to do with our current predicament? You don't seriously mean to say that she caused this, do you?”
“It worked for Platinum, and I don't think she even intended it. It will work for me.”
He snorted derisively. “Platinum was an astoundingly powerful pony in her own right. If she had not been interrupted, she could have had whatever she did work regardless.”
“You know what ponies are made of, don't you?”
He laughed bitterly. “Marshmallows and sunshine?”
She moved slowly towards the cliff. “Our bodily structures can't support themselves without magic. You know that. Our bones aren't built to bend the way they do. Earth ponies wouldn't even be able to live without it; their lean muscles are so dense that they collapse into themselves when they die. Pegasi can't fly without it. We're reservoirs of magic, Professor, generating it in our youth and losing it to senescence. I could release that magic, Professor. Every instant of power I would ever have felt, gone in a single, rapturous instant. A single display of power. Just like Platinum.”
“'Single, rapturous instant'? I'm surprised that you haven't appeared in the newspapers yet. 'Promising student Starlight Twinkle dies in tragic autoerotic asphyxiation incident! Faculty in disarray; personal tutor unsurprised, claims history of deviance.' As much as I hate to interrupt your adolescent fantasy, there is no quick fix to this situation, no panacea. Magic doesn't work that way, Twinkle. Put me down.”
She laughed. “It shouldn't work that way, but it does. You know that. You know I'd change it if I could. I'd make it work on friendship and love and harmony.” She sighed. “But it does, and I might as well make use of it. Or else there soon won't be any magic left at all.”
He took a while to respond. “How dare you?” he said, finally, his voice getting somewhat higher. “What makes you think you have the right? How dare you bring me here to make me witness the death of my most promising student, you miserable, suicidal idiot?” His voice cracked on the last word, and he took a deep breath.
“You can't prove me wrong, can you? You know I'm right, but you can't detach yourself from me and face the facts. I'm the only one who can do this. Why do you think I brought you here? I wanted you to know that I was gone so you wouldn't look for me. I wanted to say any number of things to you. I wanted to know what you thought. I've always respected you, Professor, and I knew you'd argue with me; I knew I was right as soon as you stopped arguing rationally.”
She was silent for a second.
“I met you here, Professor, because it'd be better than a letter.”
“Why?” he said, shaking his head. “Why you?”
“You said it yourself, didn't you?” She said, her smile never fading. “'A+. V. good concentration but requires impetus'. I think 'all of ponykind' is a very good impetus.”
“That's a standard bit of praise. I've written that exact same sentence for fifty other ponies, Twinkle. Fifty others.”
“Half of them think that this is just something that's going to go away in a couple of weeks. Even if they didn't, would you ask anypony else to do this?” She looked at him hard, forcing his eyes to look into hers. “Could you?”
They were both quiet for a while.
She glanced behind her. “It really is a beautiful place to jump, isn't it? You wouldn't even know what ponies do here.”
The Professor looked down at his hooves; he did so for a while, as Twinkle waited for a response. The voice that returned came quietly, almost shamefully; she'd never heard anything so sentimental coming from his mouth.
“Promise me you won't die.”
“That's the whole point of this little exercise, Professor. I can't lie to you. You always were one for the facts.” She gave him a slight smile as she stepped back; the ground went from under her and she began to fall. Fully focused, she let go of her holding spell and started a new one entirely. “Goodbye.”
He looked up as he fell onto the snow, and his eyes met hers for the tiniest moment.
She'd never seen tears from him, either.
Right before she fell into the echo corridor, a faint voice barely reached her ears against the torrent of wind. “At least promise me, you—”
The voice was lost.
She began to pray, her horn shining; she was at peace as her speech echoed about her. It was a very long way down.
“Let the sun rise as it was before.
Let the moon shine in the pitch sky.
As I go, let my soul rend itself from my body.
May my children use my bones for tools.
Let them live a life greater than mine,
built on my ashes
rested on my husk.
Let them build their warm cities around me,
let them remember the past only in tragedies.
Give my soul eternal rest
and let my body live as my children
so that I shall not die
but live forever and ever
in the kingdom of the heavens.
Amen.”
She closed her eyes.
And then she opened them in realisation, a metre from the ground.
“I promise,” she said, and pulled down the sky.
Her neck broke against the rocks and it turned a brilliant white.