Sunset looks on with astonishment at her surroundings, as this is nothing like she expected.
She honestly had no idea where she would go, as she had very little time to analyze the magic that hit her. Harmony magic is something she ever only encountered in ancient texts and her own theories. She suspected it sprung from a central source, but Celestia never talked about it, and Sunset never found it. Yet she is sure that it tied into Ascension somehow, and this is the source of her surprise and no small amount of confusion.
Sunset told Star Singer that she does not seek Ascension. While true, Sunset would not have turned it down had it happened. She thought that avenue closed to her the moment she left Equestria behind. Only upon a successful and triumphant return, with the full force of magic behind her from a seven billion strong pony population, would it ever enter the picture again. After all, in her view, Celestia's power would not be enough to counter all the future threats Equestria faced, and a new alicorn Princess would be needed.
As she slowly trots forward in this strange realm, she can feel immense power on the edge of her magical senses. Did Twilight's plan for Sunset backfire? Or did Twilight have a change of heart but had to fool the humans long enough to help spark Sunset's Ascension? No, that is wishful thinking, just her pining to have at least one member of her family understand and support her.
Sunset knew once she entered that portal by herself over twenty years ago, she cut herself off from any support. That was easier to bear when she believed Equestria as she knew it was doomed. Finding out that Equestria survived was bittersweet, and discovering active opposition to her plans sad.
Sunset stops when she senses a presence. She has no clear sense of direction in this realm. Clearly she is not meant to go to it -- whoever or whatever 'it' is -- but that it is supposed to come to her.
"I'm here," Sunset calls out.
"Sunset Shimmer."
Sunset is so shocked by the voice that she stumbles as she turns towards it. Her eyes widen, and her lips part as she stares at a pony she never thought she would ever see again. "Princess Celestia??"
Celestia strides forward and comes to a stop a few pony-lengths away. Sunset takes only another step forward before she realizes that the gulf between them might as well have been light years. Does some part of her still hope for the relationship they once had, even after all this time?
Sunset said to Star Singer "she wouldn't even have to thank me." It sounded like an off-the-hoof quip, but really, Sunset wants that thank you, not for the accolades, but just an acknowledgement that everything she did was worth it in the end. Now she does not even have that much to present to her former mentor. In reality, a partial success is no success at all.
"I failed you," Sunset says in a low voice. "And Equestria."
"No, Sunset," Celestia says. "You did far worse than that. You disappointed me. And as for Equestria, it is unlikely it will be as appreciative of your actions as perhaps you believe."
"My plans were working!" Sunset declares. "It was Twilight who interfered with them! If she hadn't--!"
"And once again, you are doing what you have been for the past twenty years: utterly missing the point."
Sunset now has to accept what she did not want to see, that Twilight's corruption stemmed from their shared former mentor. Her hopes that Celestia had come to see reason are dashed. "If you're about to go on and on about the morality of what I'm doing to humanity, you can save your breath. I've heard it more than I care to from two ponies I thought were my friends."
"I have no intention of taking that path," Celestia says. "As it is apparent that it is wasted on you. You have reduced everything to cold mathematical odds and hard equations."
"And you're doing the same thing Twilight tried to do: paint me as some sort of monster."
"What have you left me with? You are not the first to make grandiose plans based on patterns of logic, but always such plans were tempered by the heart."
"And mine is supposed to be so cold that I cannot do the same?" Sunset protests. "I care for every last human I have transformed! I even went out of my way to see to the welfare of a human family whose lives I accidentally disrupted. I'm trying to ensure that all their lives are better."
"You don't understand," Celestia says in a heavy voice. "And that is the great tragedy here. No, Sunset, I do not mean the heart to understand the morality of what actions you take. I mean the heart to leave open the possibility that your whole original premise may be wrong."
Sunset hesitates. "What??"
"Of every decision I make, the greater its impact, the more I must consider the possibility I am wrong. To fail to do so means committing myself to an action that, even if successful, was ultimately completely unnecessary and disruptive. And this, Sunset Shimmer, is why I am disappointed in you."
Sunset's mind races. She remembers the day she finally finished her great effort in determining the magical reserve of ponykind, when she wrote down her final equations and contemplated the legacy she intended to bequeath to Twilight.
"Because when you choose to take an action that will affect an entire species," Celestia continues. "You must be absolutely and unequivocally correct. Not a single premise upon which you base that decision can be wrong."
"But I'm not wrong!" Sunset cries. "I verified all my theories time and time again. What more would you have wanted of me?"
Celestia closes her eyes as if in silent contemplation, and Sunset realizes that she is falling back into old habits that she thought herself free of. She actually wants Celestia's approval. She wants to be told that she did a good job. This is the mare that tried to erase all existence of her, and yet she still wants that acknowledgement.
Yet when Celestia's eyes open, and they blaze with an almost blinding white brilliance, all Sunset can do is stumble back in shock.
Celestia's mane and tail suddenly burst into flame. She spreads her wings, and the trailing ends of her feathers glow like smoldering coals. She takes a step forward, and smoke rises from her hooves as they leave char marks in their wake even upon this ethereal realm.
"WE ARE HERE TO INSTRUCT THEE AS TO EXACTLY HOW WRONG THOU ART," Celestia's voice booms with such volume that Sunset's ears ring.
Sunset quivers, and she tries to penetrate the illusion, for that is what it must be. The sheer amount of power she senses could not possibly be concentrated in a single pony, for no pony could ever stand such power without shattering from the inside out, even an alicorn of Celestia's abilities. Or what she thought were her former mentor's abilities.
"WE SENSE THY PROBINGS, AND WE ASSURE THEE WHAT THOU SEES IS REAL"
Sunset swallows hard, her eyes glistening as all she can do is stare when her feeble attempts to deny what she is seeing crumble to dust. This is the power she had sensed from the distance when she first arrived. She had assumed it originated from this realm, but even then she could sense an intelligence behind it that she did not want to acknowledge.
"WE CAN BREAK THE DAY. WE CAN SHATTER THE NIGHT. BUT MORE IMPORTANTLY, WE CAN DESTROY THY SENSE OF INFALLIBILITY."
Here is everything Sunset ever wanted. Here is the salvation of pony-kind from all threats. Here is what would have assured her that Equestria would be safe for all time to come. It was right there, all along, and she did not see it.
"This has to be some sort of a trick!" Sunset bellows.
Celestia lifts a fore-hoof and slams it back down. A clap of thunder reverberates from the strike. A wave of power expands from the impact which flows over Sunset like a blast of scorching hot air. "WE DO NOT PLAY PETTY GAMES. THOU ART AN EVEN BIGGER FOOL IF THOU DENIEST WHAT THY SENSES TELL THEE."
"Then why didn't you tell me you could do this?!" Sunset screams as she wipes tears away with the back of a fore-hoof. "Why did you never tell me you could command such power? Why didn't you ever USE IT?!"
Celestia's expression softens, and she lowers the volume of her voice as she says, "Just because something can be done does not necessarily mean it should be done, my dear Sunset."
Sunset's voice become venomous as she says through clenched teeth, "I spent twenty years of my life at this. I tore myself from friends and family. I left them all hating me. And then you made them forget me. I GAVE UP MY LIFE FOR THIS!"
Celestia sighs and closes her eyes. She reverts back to her original form, and when her eyes open, they look upon Sunset with a mixture of worry and sympathy. "Is that all you can think of, Sunset? Of your own life and fortune? Nothing to be said of the other lives you disrupted?"
"Y-you could've told me what you could do," Sunset says in a quavering voice.
"Yes, I could have," says Celestia. "I could use the excuse that I simply didn't understand exactly what you were doing, but, really, it is beside the point. The point is, you chose an action with such far-reaching consequences based on your own research -- research you did not let anypony validate -- under the assumption that you could do no wrong."
Sunset's throat tightens, and she is unable to respond right away. She wants to claim that nopony else was at the level of her ability or knowledge to even begin to understand her equations, yet that is not at all true. The one being who could have understood them, who could have set her mind at ease with a simple, singular demonstration, stood before her in judgment.
She wipes her eyes again as she thinks back to her last conversation with Laura. Perhaps nopony will ever believe her, but it hurt to know she disrupted Laura and her family due to Sunset's own failing. Laura's last words to her had stung more than she let on, and at the revelation that none of the disruption was ever needed in the first place, it became a much deeper wound.
Yet even this pales in comparison to what she did to Fred Turner. She never intended for him to spend twenty years in a delusional state. That she found him useful in the end had indeed been a calculated move, but always with the idea that realizing the goal would be worth it.
But there is one thing that simply does not fit.
"You didn't answer my other question," Sunset says in a low voice. "If you had this power all along, why didn't you use it on past threats? Why did you rely on magic relics? And don't fall back on that can or should nonsense. I want the real reason!"
Celestia pauses as if collecting her thoughts. "The demonstration I just gave is of immense power, yes, but barely controlled. It can do more harm than good. It can defeat the most powerful foe at the price of turning a large area of Equestria into a wasteland."
"Then how can you stand there and claim all my work was for nothing?"
Celestia closes her eyes, and Sunset takes another step back, as if fearing that the next demonstration of power would be directed at her in summary judgment. Yet her former mentor's face remains calm and somewhat sad. "Had this been just a day ago, I would not have an answer for you. Yet there was one nagging detail that I could not resolve." She opens her eyes and casts a troubled gaze at Sunset. "Why would you ever be considered for Ascension?"
Sunset's pupils shrink. "I ... what??"
"Exactly what I have said, Sunset. I can sense when ponies are close. I sensed that in you before you left, before you started on your transformation research."
Sunset's heart pounds. Fear turns to rage. and it is all she can do not to leap at Celestia despite knowing it would likely be the last thing she ever did. "And you took all that away from me when you--!"
"No," Celestia says firmly. "You threw it all away."
"You're not making any sense."
Celestia frowns and steps forward until she looms over Sunset. "Then let me clear it up for you, my little pony. I took another look at your equations, especially those for Twilight in estimating her potential power as an alicorn. It was then I finally realized a possible application for your research, and a reason you were considered for Ascension: you could have solved the problem of the second threshold."
Sunset blinks. "The what??"
"I did not always command this power. I developed it some time after becoming an alicorn."
"My research clearly showed that you built up your power over time," Sunset says with growing impatience. "It simply never predicted such a spike in--"
"Sunset, until I am finished or ask you a direct question, kindly shut up."
Sunset stumbles back another half-step, her utter shock at such a simple rebuke enough to silence her for the moment.
Celestia begins to pace about her former student. "You may think yourself brilliant, but what you really are is short-sighted. You chose a course of action so early on that you blinded yourself to other possibilities. I noted something very interesting in your research. Not once did you ever extensively explore the issue of my immortality. Equestrian history is rife with mages attempting to find the secret of eternal life, and nopony ever succeeded. Did you ever wonder why that was?"
Sunset swallows. "I noticed you haven't told me where your power--"
"ANSWER THE QUESTION!" Celestia roars.
Sunset's ears flatten hard against her head, and she struggles not to cringe. "I-I didn't think it was important! I thought it was something that I would work out later."
"Wasn't important?! When it could have led you to question as to whether I possessed more power than was immediately apparent? Or were you so far along in your grandiose idea to transform an innocent species that you just didn't want to see anything that could possibly hint you were in the wrong?"
"Everything I did was for you!" Sunset yells. "Everything I did was to further your power, in order to protect Equestria!"
"At which you failed."
Sunset's lower lip quivers, her mouth open as if to protest, but no sound emerges.
Celestia flares her wings. "You have no idea what it is like to possess the power to crack Equestria in two and have little means to use it. Every powerful threat that has come up, I have had to watch myself, to stop myself from thinking the situation so dire that I would have no choice but to use that power. The closest I ever came was Tirek, and even then it took Luna and Cadance to convince me to trust Twilight with our combined power to hide it from him. You could have used those twenty years helping me find a way to control that power. You could have given us BOTH everything we ever wanted. You would have a ruler you could worship as a goddess -- worship I STILL would not want or desire -- and I would have the means to protect my ponies from any threat." Celestia snaps her wings to her side and adds in a lower but no less angry voice, "And you would have likely earned a set of wings for your efforts."
Sunset's thoughts are too jumbled for her to make a coherent reply. All the protests she could make ring hollow. At the beginning, she wanted to protect Equestria. Then it became protecting two species. She feels like she made the ultimate sacrifice in leaving her former life behind.
And now she finds herself asking the same question Laura asked of herself: what if everything she thought she knew and believed is wrong?
"Please tell me," Sunset finally says in a plaintive voice. "Where does this power come from?"
"It's exact origins are unknown to me," Celestia states in a calmer voice. "I call it 'the second threshold,' a point after Ascension when a conduit opens to this power. It is at that point I became immortal."
Even in the depths of her emotional turmoil, Sunset's mind works with almost cruel efficiency. She can picture the equations before her that led her to attempt to transform an entire species. The idea that magic is tied into life itself is a premise known from the very early days of Equestria's magical awakening. Now she sees how those equations could have been extended. She could see how an infusion of power from another domain could somehow entwine itself around the life force, renewing and replenishing it.
Again, the protest threatens to spill to her lips, that she has the benefit of being told about this power that Celestia has kept secret. She could pummel her former mentor with accusations of holding out on her. Yet how many times has Celestia done that in the past, and Sunset always came through with the answer anyway?
"And had you explored my immortality, I have every confidence you would have discovered everything I have just told you," Celestia says in a voice more sad than angry. "And look where we are now instead."
"I thought I was right," Sunset says in a firmer voice as she struggles to regain the initiative. "I thought I had the only possible solution to the problem. I wasn't looking for personal glory. It was never about that."
"I never said it was, Sunset." Celestia utters a heavy sigh. "It is a common failing among ponies that we see the world through our own biases. I believe that's what you did. You were always trying to push the boundaries of magical knowledge, and you had the golden opportunity to do so here. Nopony had ever managed a permanent transformation spell, but you saw it could be done."
"Because that was the only way I saw to achieve my goal," Sunset says.
"Yes, you've made that abundantly clear. Tell me, Sunset: I know you dismissed my concepts of can and should just now, but what about back then? Did you ever give even a moment's thought to it? Did you ever ask yourself if the ultimate outcome was really worth the turmoil you created?"
"What difference does it make now?!" Sunset explodes. "When it's already been said and done? I don't exactly have a time travel spell where I can go back and change anything, now do I? It's over."
"Because what you were thinking matters," Celestia says in an urgent voice. "It matters to me, and it matters as to your ultimate judgment."
Sunset's eyes widen. "Judgment? And just who is doing the judging?"
"A very good question, Sunset Shimmer. A very good question indeed."
"You're not ... you're not even thinking of letting the humans--!"
"Does that idea frighten you?" Celestia asks.
If the tone were any less sincere and earnest, Sunset would suspect Celestia is baiting her. She cannot answer with the truth. She has already let herself look disgustingly weak before Celestia, and all because her former mentor ran her around in circles of both emotion and logic.
Yet those equations she bet her entire life upon still spin in her head, forcing her to see the further possibilities that she ignored two decades before.
"You claim you have the interests of the humans at heart," Celestia continues. "Surely you would want the chance to explain yourself and your thinking to them as assuredly as you're trying to do so with me."
"Stop playing games," Sunset snaps. "If you've been talking to Twilight, you know perfectly well how they'll react, especially considering how they've already tried to kill me twice."
"And you truly believe they have no right to act this way?"
"If I had been allowed to finish, none of this would matter!" Sunset cries. "They wouldn't have any need for violent justice! They wouldn't have any needs at all! They would have had peace and plenty for eons!"
"That's what you claim you believe now," says Celestia. "Is that what you believed back then when you first conceived of your plans? Did you approach it thinking that you were improving the lives of another species? That you were helping them as much as your own kind?"
Sunset's mind spins with so many memories of her many conversations with Star Singer on the subject that she hesitates.
Celestia steps up to her former pupil. "Or did you simply use it as a means to prevent yourself from ever doubting what you were doing, from ever questioning whether this was truly the right thing to do, from silencing any of the guilt that--"
"There was no guilt," Sunset utters in a low voice. "There can never be any guilt. Guilt is just another name for doubt. There can be no guilt if there is no doubt."
Celestia tilts her head. "I do not quite understand."
Sunset stomps a fore-hoof. "In all the time I was your student, did you once see me appear as anything but confident and self-assured, even when I made mistakes?"
"Yes, it was one of the things which brought you to my attention when I was seeking a student."
"Exactly," Sunset says in a low but firm voice. "Ever since that day I gained my cutie mark, I realized I had the potential to be a powerful unicorn. Having such power means I can't afford to doubt myself. I can't afford to feel like I don't have all the answers."
"And where did you get such an idea?"
"From you."
Celestia remains silent and thoughtful, and she nods in a bid for Sunset to continue.
"I admired you from an early age, even before I earned my cutie mark. I saw you as the epitome of self-confidence and self-assuredness. Not once did you ever waver. You acted as if you knew exactly what you were doing at every step. And when I became your student, you continued to act in the same way. You never even hinted at any of the supposed doubts you had about anything you did."
Celestia utters a forlorn sigh. "I already realized that I should have developed a less formal relationship with you, and these are things I later corrected when I took on Twilight as my student. I have already accepted some blame in the way things have turned out for you."
"I'm not looking to lay blame. I like feeling confident. I don't like doubting myself." Sunset pauses. "Did you know that the town in which I ultimately chose to spread the virus was not my first choice? Do you want to know why I changed my plans? All because of a single human girl."
Sunset's eyes glisten as she recalls her last conversation with Laura. She is mindful of Celestia's curious gaze, and she suppresses any further emotional reaction. Despite the sentimentality in her words, she cannot let it go beyond that. She cannot start to doubt herself after all this time. "I had accidentally triggered a tornado while doing research into magic energy storage, and a five year old girl witnessed it. I altered her memory and sent her back home and thought that the end of it."
Celestia considers. "Jenny Tanner?"
"Yes," Sunset replies. "Yet when I checked on them later, I discovered that while Jenny retained no knowledge of the incident, it was her older sister Laura who became traumatized over it. She went from a girl who could have become a confident young woman to someone riddled with self-doubt."
"And you felt no guilt over this?" Celestia asks.
"I felt regret, not guilt. But more importantly, I saw myself."
"I do not understand."
"Have you ever been told the truth about the time I gained my cutie mark?"
"Twilight witnessed a memory of your mother with the help of Luna," Celestia explains. "It was when you first created magical plasma. You seemed very confident of your work."
"Well, I wasn't," says Sunset in a softer voice. "My mother obviously idealized the memory. I stumbled over myself, over my words, over everything. It was a sheer miracle that I achieved the result that I did. But once I did, and I saw the potential I had, I realized I had no business doubting myself. That's what I saw in Laura. I sensed that her transformation would make her very powerful and very capable, but only if she stopped doubting herself."
"So you stayed in Lazy Pines?"
"Yes, specifically so I could help guide her when she transformed." Sunset frowns. "So don't you dare even imply that I don't care about this species. I went out of my way to see to the future of a single human."
"And yet you are once again missing a crucial point," Celestia says. "Your doubt when you were young was all your doing, as was the confidence you gained later. Laura's self-confidence was all your manipulation, as was her doubt in the first place."
"What difference does that make when the end result is the same?" Sunset says in exasperation. "I made a mistake, and I owned up to it and fixed it."
"And now we come full circle," Celestia says in a harder voice. "Living beings do not exist for you to 'fix' them. That is the attitude you appear to have adopted concerning the humans. They are just tools to you in the end. Properly and perhaps even lovingly maintained, but tools just the same."
Sunset wants to argue the point with Celestia, but to what end? To force some sort of acknowledgement from her that would never be granted if they argued until Earth's sun went dark? Yes, the humans were a means to an end for her. She wants to believe her care for them is genuine. Certainly it is eminently practical. Why abuse the very beings who are serving a grand purpose?
And yet what continues to nag at the back of her mind is the idea that none of this had to happen. Her logical mind refuses to dismiss the possibility that exploring Celestia's immortality would have led her down a different path.
"You want me to admit that I made a mistake in choosing the solution that I did?" Sunset says in a voice that quavers slightly despite her attempts to steady it. "Then I will. I admit the possibility I could have neglected an avenue of research that would have led to a different solution." She narrows her eyes. "But had I pursued that, and had it turned up empty, and this solution was still viable, I would have not hesitated in pursuing it."
"I-I've heard enough," a choked female voice emerges from the thin air. "Please ... I don't want to hear anymore!"
Sunset's mouth drops open, and her pupils shrink. "That voice ... it sounds like ..."
Celestia gives Sunset a forlorn look as her horn glows, and a concealment spell is dispelled. A unicorn mare appears beside her.
"What?" Sunset says in a tiny voice. "M-Mom?!"
Sunset Glow steps forward, her face a mix of sadness and anger. Sunset nearly gives into the urge to dash up to her mother and hug her, yet something about her mother's stance holds her in abeyance.
"They told me something about you that I couldn't believe," says Glow in a voice unsteady but rising in both anger and despair with every word. "Until I heard you speak the way you did just now."
"Mom, what are you talking about?"
"I'm talking about Derpy!" Glow cries, her eyes tearing. "Did you really transform a griffon child into a pony just to further your research?!"
Sunset takes a deep breath. "Mom, please, you don't--"
"Just answer my question!"
"Yes, I did, but--"
All the magical reflexes and power in Sunset's possession were not enough to see the back of Glow's fore-hoof until it struck her with a resounding slap across her muzzle. Sunset stumbles back in utter shock, raising a trembling fore-hoof to the side of her face.
"You're not the daughter I raised!" Glow wails. "My daughter would never EVER tear a child from her parents for ANY reason! Despite everything I was told about what you were doing, I had hoped at least that detail was wrong. Maybe I could accept everything else you did as getting too wrapped up in your grandiose plans, that you saw the forest but not the trees. That's easy enough to understand, b-but this--!"
"What are you getting at?" Sunset demands in a quavering voice. "Why are you harping on this one detail?"
"Because that's all it is to you is one little detail. You used her for your own ends. You did that RIGHT FROM THE START! Now you expect me to believe you actually care for these humans you're transforming?"
Sunset extends her magical senses in increasing desperation, searching for anything that could expose this as a ruse. Illusion spells, changeling magic, anything. Instead, she is confronted with the hard reality that this is really her mother, a mare who was nothing but supportive her entire life. Some of the very words Sunset used with Laura she had one heard from Sunset Glow.
"Princess Celestia was right," Glow says in a despairing voice. "They're just tools to you. They're just there for you to manipulate. You might as well have been the racist that you let your family believe of you. I thought there would be nothing worse than that. I was wrong."
"I care for the humans," Sunset says in a strained voice.
"I don't believe you. How can I trust anything you do or say? I have to assume it's just part of your scheme, a calculated response to gain sympathy from me."
Sunset's throat is too tight for her to speak further, but even if she could, she has no words with which to defend herself. It was easier to accept rejection from her family when she believed they were as good as dead, or living in such bad conditions that Sunset's triumphant return would render all debate over how she got to that point moot. Since first learning Equestria survived, Sunset had in the back of her mind the desire to reconnect with her family. She first hoped to do that through Twilight by eventually convincing her of the merits of her plans.
Sunset said she gave up her life for her work, words which now had become prophetic. If her own mother cannot be swayed, she truly has nothing left, not even a successful execution of her plans to show for it.
"You started life as a caring, wonderful filly who was a complete and utter joy to your family," Glow says in an increasingly shaky voice. "Now all I see is a cold and calculating mare who might as well be a completely different person. I have to wonder how you made that transition. At what point did that caring pony become just a facade, just a carefully crafted mask you wore so nopony would ever be the wiser?"
"Stop it!" Sunset screams as she wipes away tears. "I'm tired of being cast as a total monster! I'm not!!"
Glow regards her daughter with a look that Sunset dares to believe is the first glimmer of sympathy. "No, Sunny, you're not a monster. A monster feels glee for the destruction she causes. A monster I could understand. You just don't care, period." Glow utters a long sigh. "Maybe you really have convinced yourself that you do care. Maybe that makes it easier for you. I don't know. I don't know YOU anymore. I look at you, and I don't see the daughter I thought I had raised."
Sunset falls to her haunches and lowers her head.
"I'd do anything to get her back," Glow says, her voice cracking. "All it would take would be for her to admit that she was wrong, that transforming a species against its will was wrong, that tearing a child from her parents was wrong, that deceiving her parents, her friends, and her mentor was wrong."
Sunset doesn't know what to do or even feel. She feels grief, but for what? For the shattered relationship with her family? For the failure of her plans? For the complete lack of anything to show for all her work? For the failure to get others to understand? For the missed opportunity that would have avoided all this?
Or perhaps grief over the possibility that her mother is right?
It is too much for her to take in and consider all at once. She cannot make what everypony wants of her happen in an instant. She raises her eyes to her mother and blinks away tears. "I c-can't give you what you want. I don't know if I ever can."
Celestia steps forward. "Sunset, this is not the time to underestimate yourself. That you are even contemplating--"
"Shut up," Sunset says in a weak voice that is barely audible. "Just ... shut up. I-I've heard enough."
Glow bites her lower lip as she stares at Sunset with shimmering eyes. She finally whips her gaze back to Celestia. "Please, Princess, can we take her back to Equestria?"
Celestia sighs. "Sunset Glow, we spoke of this before we arrived."
"But that was before when we thought there was no chance of getting through to her! Maybe if we take her back, maybe if we give her more time, she--"
"No," Sunset says firmly.
Glow gives her a stricken look, and only in that moment does Sunset dare to believe that her mother still has any love left to give to her. It shatters her own heart to know she cannot accept it.
Sunset rises to her hooves. "You'll only be setting yourself up for disappointment."
"But you just implied that maybe with enough time, you could--"
"And how much time is enough?" Sunset exclaims. "A day? A month? Years? Decades? Maybe this is just playing to the perception that I see everything in numbers and equations -- and ... maybe that perception is right -- but I can calculate the most likely outcome: all I will see is my failure. All I will do is ask myself, what if I had been allowed to finish what I started? What if I had created something incredible?" She gives Celestia a morose look. "And I will alternate between that and wondering what I could have achieved had I chosen to pursue the alternate solution."
Tears start trickling from Glow's eyes again.
Sunset turns to her mother. "And you may be waiting all that time to hear words from me that may never come. I guess you're right. I'm not the daughter you once knew. I did become cold and calculating. I realize now that I thought I had to. If I was to save Equestria, I had to make absolutely sure I did not waver in my beliefs or actions." Her voice softens. "Everything else is a distraction."
"I don't want to be right!" Glow screams.
"It's better that you have the pain of being right about me than the extended pain of waiting for a redemption that may never come." Sunset turns to Celestia. "Send me back to Earth, please."
"N-no ..." Glow whimpers.
"Sunset Shimmer," Celestia says in a sad voice. "You should be aware of a decision that has been made concerning--"
"Twilight is going to let the Earth authorities prosecute me," Sunset says tonelessly.
"Yes. But I fully intend to be at your trial, and while I cannot and will not condone your actions, I will speak of what has transpired here. Perhaps in the time leading up to that point, you will find it in yourself to come to the understanding for which your mother has expressed her hopes."
Sunset's eyes glisten as she looks at both her mother and her former mentor. She once thought she would never see them again. Now she knows for sure. So this is indeed a judgment of a sort, even though she feels nopony else is fit to judge her.
She simply nods an acknowledgement to Celestia before saying to Glow, "Goodbye, Mom. I'm sorry I wasn't the daughter you wanted."
Glow can only make a choked noise while her tears flowed.
Sunset thinks she sees a tear form in one of Celestia's eyes before Sunset is once more cocooned in rainbow light.
Twilight glanced nervously at the assembled armed forces that had moved in soon after she and her friends had used their Rainbow Power on Sunset. She can sense their growing impatience as full night approached. It had taken a great deal of effort on her part to convince them to let her friends do this in the first place, culminating in a demand to speak directly to the President before it was authorized. Some saw it as an attempt to remove Sunset from the reach of their justice.
A searchlight gleamed off yellow and pink as Fluttershy flew in and landed nearby. "Laura is safely back at the settlement now, Twilight." She smiled. "The humans were very helpful in keeping their bright lights on us the whole time so we could find our way."
Twilight decided not to correct her friend's naiveté. More likely, they used the lights to keep track of them as if they were enemy fighters. The clearing itself was awash with light from the army vehicles, almost as bright as day. Nothing was getting in or out without the humans knowing about it.
Applejack stepped up to Twilight. "Is it jus' me, or are these here humans more antsy than a coupla fleas on a hot roof?"
"'Antsy' does not even begin to describe it," said Rarity in a subdued voice.
Rainbow Dash looked around. "Geez, is everything around us a freaking weapon?"
"Most likely, yes," said Twilight. "Or they contain weapons or have systems for summoning more weapons."
"Wow. Overkill much?"
Fluttershy's ears flattened slightly. "Um, they do know we're not the enemy, right?"
"Sure they do!" Pinkie Pie piped. "I think. Well, there was that bit about Twilight warning me not to bring my party cannons."
"I'm not worried about what they'll do to us," said Twilight. She looked over to the charred mark on the ground where Sunset had vanished. "I'm more worried about what they'll do to Sunset when she gets back, because that's where most of their weapons are pointed."
"I thought we had worked this out with them," Starlight said. "They give her an ultimatum, and I unmark her for good this time now that I figured out how to modify the enchantment on the jar to counter the buffeting effects."
"And if she doesn't accept that ultimatum?"
"Then we go all Rainbow Power on her ass again!" said Rainbow Dash.
"We can't," Twilight said. "Celestia took a great deal of time and effort to link us to the Tree of Harmony across the portal, and it was a temporary link only. We weren't even a hundred percent sure it would work. Only the knowledge gained from Sunset's energy conduit spell helped us make it possible at all. Remember, I never intended to try to use it in the first place. The original plan had been to try and contact Sunset while she was sedated. Her escape changed everything."
"Surely there's something we can do?" said Rarity.
"I think it's going to be mostly up to the humans now, and that's what I'm afraid of."
"How's that now?" Rainbow asked. "I thought you said you had the humans' trust."
"I do," said Twilight. After a pause, her eyes turned troubled. "At least I did. Thanks to Sunset escaping, they're extremely suspicious and wary right now. When I first presented our plans concerning Sunset, I got pummeled with all sorts of questions about our Rainbow Power. Why didn't you tell us you had this power? Why didn't you use it before? Why don't you use it to neutralize her now? If worst comes to worst, can you kill her with it?"
Fluttershy gasped and paled. "K-kill her??"
"They're seeing Sunset as a being who is destroying their world. They wanted to keep her alive to face justice, but they're not willing to take a chance she'll completely destroy them as a species. She's already triggered an acceleration of the ongoing transformations. I'm having a very hard time explaining to them what magic can and can't do."
"Heads up!" Applejack cried as a low whine rose from the center of the clearing. "Somethin's happenin'!"
Twilight turned and saw rainbow light beginning to swirl over the char mark as the whine grew louder. The soldiers saw it as well, and orders were shouted and weapons brought to bear.
The rainbow light swirled faster, collapsed in on itself, and lighted the clearing with a nearly blinding flash, leaving behind Sunset Shimmer.
At once, an amplified voice blared. "Attention Sunset Shimmer. You will remain where you are. You will submit yourself for unmarking. You will submit to being sedated. If you move from that spot, or attempt to use magic, or resist in any way, we will open fire."
"Dang, they're serious," Applejack said in a low voice.
Sunset did not respond. She simply stood there, staring straight ahead, her gaze directed just slightly off to the side.
"What is she doing?" Starlight whispered.
"Calculating her options, most likely," Star Singer murmured.
"Options? What options? She doesn't have any!"
"You don't know her like I do. If she thinks she has a way to do things on her own terms, she won't hesitate to try it."
"No, this has to end now," Twilight declared. She cantered forward. "Sunset, you have to agree to their demands! You don't have a choice now!"
Sunset turned her head towards her niece. Twilight's breath caught when she saw Sunset's eyes. Had she been crying?
Sunset's lips slowly curled into a slightly trembling smile. "Nonsense, Twily. There are always choices. Allow me to make mine."
"What in tarnation is she goin' on about?" Applejack muttered.
"I-I don't know," Twilight said in a quavering voice. "Surely even she realizes--"
"She's moving!" Starlight cried.
"Right at the humans with the big guns??" Rainbow cried. "Is she out of her mind?!"
Twilight had to move closer to believe what her eyes were telling her. "Sunset, stop! You're supposed to stand--!"
She was drowned out by the amplified voice. "Sunset Shimmer, this is your final warning! Stop at once, or we will open fire!! I repeat, do not move, do not use magic--"
Sunset's horn began to glow.
"She's insane," Starlight said in a hollow voice. "She's got to be."
"Hang on," said Rarity. "Is that just a simple light spell?"
Twilight had sensed that as well, and with dawning horror she realized what Sunset was trying to do.
A second later, a thunderous roar rose as the soldiers fired.
They were met with a shield.
It was not of Sunset's doing.
Sunset blinked and stared at the purple energy which shimmered around her, bursts of light flaring as wasted ammunition was detonated or deflected. Sunset tried to push out of it, only to find that it followed her.
She whirled around. "Twily, what are you doing?!"
Twilight's horn blazed. Her mane and tail moved as if a wind were pushing them. Her eyes were brilliant white. Her friends shouted towards her, but she could barely make out their voices over the constant roar from both the humans' guns and the power she commanded. "I'm not letting you do this, Aunt Sunset! I'm not letting you kill yourself!"
"This is my choice to make!" Sunset roared. "Not yours!"
Despite standing this close, Twilight could barely hear Sunset. She cast another spell, and her amplified voice boomed out, "I BEG OF YOU TO STOP FIRING AND LET ME SPEAK WITH SUNSET! I AM NOT LOWERING MY SHIELD UNTIL YOU GIVE ME THIS CHANCE!"
And, miraculously, the gunfire ceased, leaving a ringing in her ears.
"Aunt Sunset--" Twilight started.
"Just leave me alone!" Sunset screamed. "I've had enough."
"You don't need to do this!"
"You keep saying that, and it makes no more sense now than it did when you first said it," Sunset said. "I know all about you turning me over to the humans. You and I know what will happen in the end."
"It might not be that way," Twilight pleaded, though even she knew the chances of Sunset living through a guilty verdict were very slim. "But they are the best ones to judge you."
"I will not be judged by them. I will not be judged by you. I will not be judged by Celestia, or my mother, or anypony else from our family. I, and I alone, will be my judge."
Twilight saw the tears welling up in Sunset's eyes. "If you've come to realize what you've done is wrong, it doesn't mean you have to end your life."
"And as I thought, you leapt to the wrong conclusion," said Sunset as she wiped an eye. "The problem is, Twily, I don't know if I was wrong. I am a complete failure."
"Nopony is a failure, no matter what they've done."
Sunset continued as if Twilight had not spoken. "I failed at my plans. I failed to find a way to protect Equestria into the future. I failed Celestia. I failed my mother. I failed you. Most of all, I failed myself. I have no clue who or what I am supposed to be now. I have all these people telling me what I should feel about what I've done, and no way to make it the way I want to feel about it."
"These things take time," Twilight said, but she realized the irony of her own words.
"Time I don't have," Sunset said in a lower voice. "Either way, I'm going to die. I'll die being the same pony I am now. Why delay the inevitable?"
"All ponies can change!" Twilight thrust a hoof towards her friends. "Look at them! Every last one of them has changed themselves for the better. Look at Starlight. She started out as an enemy, and now she's not only my dear friend, she's my student. If she can do it, you can as well!"
Sunset cast her gaze at Twilight's friends, and she let out a slow sigh. "The problem is, Twily, that they wanted to change. I'm not at that point yet. I don't know if I can. I don't know if I'll have time. And even if I do, what good will it do me?"
"If you really want the chance, you can do something that will prove to them you want to change, and maybe they'll give you that time," Twilight declared. "Help me. Help me stop the ongoing transformations. Help me find a way to change the transformed back to human. You're a powerful mage, I know you can do these things!"
Sunset gave her a humorless smile. "And therein lies the problem. I need that desire for change. I need to want to help you. Everypony who pegged me as a cold and calculating pony were absolutely right. All I can see is the chance that if things continue as they are now, my plans still have a chance at success. I've been in this mode for so long, I can't just step out of it all at once."
"All I am asking is to give yourself a chance," said Twilight in a desperate voice. "Yes, it might not work out in the end, but isn't a slim chance better than no chance at all?"
Sunset glanced around. "Did it strike you as odd, Twily, that the soldiers were so willing to stop firing at your request?"
"They did so because they trust me," Twilight said.
Sunset returned her gaze to Twilight. "Anyway, I suppose taking the slim chance over no chance is a measured calculation befitting my persona, wouldn't you say?"
"Yes, I would," said Twilight with relief.
"And here is another calculation, though I imagine it won't appear as such at first," said Sunset. "Apply the Starswirl Reverse Tensor technique on the original spell matrix in the device."
Twilight blinked. "Huh? What will that do?"
"Reveal a means to slow the accelerated transformations I triggered earlier."
Twilight gasped. "It's that simple??"
"Triggering the acceleration too early is dangerous, so naturally it would have a simple means to reverse it. You would've figured it out yourself with enough time."
Twilight smiled. "Thank you! I knew you could find it in you to help. Will you come quietly now?"
"I will. Under one condition."
"Condition?"
"Don't sedate me."
"But--"
"How am I to have the time contemplating what I have done if I'm unconscious the whole time?" said Sunset. "That doesn't make any sense. I'll submit to the unmarking, but not the sedation."
"I don't know if I have the power to negotiate that," Twilight said.
"Try," Sunset said. "But in the meantime, lower the shield as a mark of good faith."
Twilight desperately wanted to trust Sunset now that there was a chance she might redeem herself somehow. She knew it was a long shot herself. Her mind raced with possibilities on how this could be some sort of trick. Sunset knew Twilight could offer no guarantees, and that she might have to be sedated anyway. There was nothing more Sunset could do once unmarked.
"Starlight, come over here, please," said Twilight.
Starlight cantered over, giving first Twilight and then Sunset a dubious look.
"I'm going to lower the shield. You're to cast your unmarking spell on her at once."
"Got it," said Starlight as her horn started to glow.
Twilight turned to Sunset. "I'm sorry it has to be this way."
Sunset smiled faintly. "So am I. And, Twily?"
"Yes?"
"Thank you for giving me a choice after all."
Twilight smiled, though something seemed off about Sunset's voice. She dispelled the shield, and she sensed Starlight beginning to cast a spell that was never completed.
The distant crack came almost at the same time that Sunset's chest exploded. Twilight flinched, her coat splattered with crimson, the coppery stench of Sunset's blood filling her nostrils as Sunset fell.
"NO!!" Twilight screamed as she dived for the ground next to her Aunt.
Sunset heaved a liquid breath as blood bubbled from her lips, joining that pooling on the grass from the open wound in her chest. "Th-this is for the best, Twily," Sunset wheezed. "I knew th-they wouldn't n ... neg ..."
Her body stilled. Her eyes stared lifelessly forward.
Twilight's mouth dropped open, her eyes wide and glistening. Behind her came a gurgling noise followed by the sound of a pony vomiting to the grass. Her own gorge would not rise. She felt nothing but utter shock, like this had to be a nightmare, and she simply awaited the arrival of Princess Luna to dispel it.
Footsteps approached. "I'm sorry, Twilight."
Twilight's head snapped up, and her gaze fell on Anthony Heller.
"This wasn't something we--" Anthony began.
Twilight leapt to her hooves and snapped out her wings. "WHY DID YOU DO THIS?! She was coming along peacefully!"
"Twilight, we heard everything Sunset said," Anthony said in a strained voice. "She was in no position to negotiate, and she refused sedation."
"YOU DIDN'T HAVE TO KILL HER!" Twilight roared.
"This decision was not mine to make!" Anthony said. "We were both told that it was too risky to give her any sort of leeway."
"She was willing to meet you partway. She even gave me some help. She was willing to compromise. That's how it works on my world!"
Anthony sighed and rubbed the back of his neck. "And sometimes it does on our world as well, but we couldn't take even the smallest chance she would be free to disrupt recovery efforts. Again, I did not make this decision, Twilight, it was made for me, and it was done out of defense of humanity."
Twilight wanted to rage at him. She wanted to rage at the humans who were so scared that they felt they had to pass summary judgment, that they didn't stop to think that just maybe Sunset could be made to see her mistakes.
But then she remembered the most recent numbers Sandra gave her of people who would could become full ponies, knowing full well that thanks to Sunset, 'could' had become 'will' for at least some of them despite the tiny scrap of knowledge Sunset had tossed her way. Maybe even that was a lie.
She went over Sunset's own actions and her last words. Sunset knew they wouldn't negotiate the point about sedation. Of course she knew. She's been on this planet for over twenty years. She knew the humans better than anypony. It made sense. This was all Sunset's doing, her own decisions, right to the very end.
Judgment had indeed been passed, and it had been done by Sunset herself. Just as she never willingly gave up control of events, she refused to give up control of her ultimate destiny. It relieved Twilight of the burden of having to follow through on her decision. It took a dangerous variable out of the equation and would let her focus completely on recovery.
Yet when she looked down at Sunset, all she could see was a once beloved family member who now lay dead.
Twilight fell to her haunches and wailed her grief to the heavens. Her friends rushed over to her, but Starlight got there first, and she drew Twilight into a tight embrace. "I'm sorry, Twilight," Starlight said in a shaky voice, her body trembling almost as much. "I'm so sorry."
"It didn't have to happen this way," Twilight cried as tears streamed down her face. "Wh-why couldn't I make her see reason?"
"I don't believe this!" Rainbow Dash yelled. "They just killed her?! We never did that to an enemy before! Never!"
"Twilight destroyed Sombra," Rarity said in a soft voice.
"Yeah, but ... you can't ... that's different!"
"In a way, it's not," Rarity declared. "Sunset and Sombra brought on their own demise. Sombra gave Twilight no choice, and Sunset ..." She let out a windy sigh. "... made her own decision."
"I-I shouldn't have let this happen," Twilight whimpered. "I sh-should have seen what she was trying to do."
"I reckon nothin' woulda changed that pony's mind," said Applejack. "It's not yer fault, Twi."
"No, it's not," said Star Singer in a quavering voice. She wiped away tears with the back of her hoof. "You couldn't protect her from herself forever, and the humans can't control her without putting her under, which she refused to submit to."
Twilight lifted her head. "But if I had devoted time to figuring out a way to contain her--!"
"Then you wouldn't have had time to work on distributing the counterspell," said Starlight. "You can only do so much."
"I-if I brought Celestia here, she'd have the power to--"
"And bring another all-powerful pony into their midst? Yeah, that would've gone over well, considering how much trouble you had getting them to agree to using Rainbow Power."
"Not to mention she'd probably get shot at as well," Rainbow muttered.
"Rainbow, now is not the time," Rarity snapped.
Twilight realized two of her friends had not chimed in, and when she looked past the others, she saw Pinkie Pie standing beside a rather pale Fluttershy, a puddle of pony sick in the grass nearby.
"I'm the last one ta ever tell somepony not to grieve fer a loved one's passin'," said Applejack. "But tomorrow mornin' ya gotta be ready ta cast that counterspell. The humans are countin' on ya."
Twilight took a deep breath and wiped her face with the back of her fore-hooves. She looked towards the soldiers who still ringed the clearing. She wanted to resent them for what they had done, but she had trouble summoning up the rage. They were protecting the existence of their species. How could she fault them for that?
Her lingering guilt over the death of Sombra seemed almost trivial by comparison.
She turned to face the others. "You're right, Applejack. And there's even more at stake now. Casting the counterspell is only the tip of the iceberg."
"We'll be here for you," Rarity said.
Twilight saw Pinkie and Fluttershy approaching. "Are you all right, Fluttershy?"
"I think so," Fluttershy said in an even more whispery voice than usual. "I'm so sorry, I just couldn't ..."
Pinkie wrapped a fore-leg around her friend and squeezed gently, her mane partially deflated. She nevertheless gave Fluttershy a small smile. "It's okay. Things will get better."
"Yes, they will," Twilight said. "They have to."