Twilight was frozen rigid where she sat, paralysed with shock. In front of her, a coded mass of parchment sat, the yet-to-be-deciphered instructions on how to take control of any pony in the world. Even one as powerful as the Princess of the Night. To her right, Princess Luna hovered with powerful beats of her wide wings, stirring the leaves of the tree into sibilant whispers. The sunlight was eclipsed by the cloud of her mane and tail, flowing masses of darkness and distant stars.

"Now, Twilight Sparkle, you will come with me," she intoned, her voice filled with unshakable intent.

"No. Whatever you believe, you are the one who is going to leave."

Zecora moved so quickly Twilight barely saw her; she was just suddenly there, obscuring her view of Luna. Her body was tensed, ready to fight, even though she had nothing in her hands, and wore only her delicate nightie.

Luna stepped through the window and landed on the rug, folding her wings behind her. She wore nondescript dark clothes that covered her cutie mark. "I know of thy beliefs, Zecora. You wouldst think thyself loyal only to Twilight Sparkle. Even so, there may be hidden instructions which you do not know, and do not dream of. You must remain here."

"Do you claim to serve her too? You claim that she may trust you?"

"I do. I cannot answer any other of thy questions. The risk is too great." Luna's eyes were hard, and she spoke unflinchingly.

"I do not believe what you say is true. You are here to steal her mind anew." Zecora glared in return, moving in tandem with Luna to keep her from seeing Twilight clearly.

"I must take her far from here, where it is safe. As much as I admire thy spirit, you cannot stop me, Zecora."

"You may be surprised if we come to blows. I have powers I have yet to disclose."

"It may be that it would be safer to put you down now, so that I may speak to Twilight alone."

"Try to defeat me, if you dare. We shall see how well you fare."

Twilight, who had watched the confrontation spiral out of control with her mouth open, unable to move or think, suddenly found her voice. "Stop! Just - stop it!"

Zecora glanced back, then focused on Luna's face again. Forced to obey, she lowered her hands and stepped aside, though she continued to protest, "Her fealty is mere pretend! It is you I must defend."

"I have served Twilight with more loyalty than any, thyself included, since my sister took away her memory of us-" Luna began heatedly.

"Stop!" Twilight said again. Both ponies fell silent, though reluctantly. "Princess, what are you doing here? How did you know? Do you - remember?"

Luna tossed her mane. "I remember all that you have done to me. Thy instructions to forget what you had had me do while in the presence of my sister have protected me. I have watched you, these long months, spying upon you whenever I dared whilst I maintained the pretence of touring Equestria. I was certain that you should not be defeated so simply, not after you hadst conquered me. Your dreams hinted that you had remembered, and I travelled here as swiftly as I could. My frustration that you had not the charm, had not rediscovered the means by which I might restore you, was great. Now, at last, your preparation and my vigil have come to an end. You must come."

Twilight bit her lip. She hadn't seen Luna in months, certainly not since the revelation that she had placed her under a thought-controlling charm. She was... embarrassed, and afraid of what Luna might want with her, that much was definitely true, but that wasn't all of it.

She was curious.

"Princess Luna. If I refuse to go with you, or order you to stop trying, what will you do?" she asked, surprising herself with how level her voice was.

"I shall have no choice but to compel you to accompany me, Twilight."

"Even if I ordered you to stop?"

"You chose to allow me to disobey your commands, if a matter was of dire importance. The restoration of thy memories and self takes precedence above all else." Luna spoke firmly and matter-of-factly.

It was impossible to discern whether she was telling the truth, or merely justifying her obedience to another's will over Twilight's. In the end, the result was the same. She didn't have a choice.

"I'll go with you," Twilight said finally.

"I am pleased that you are able to agree, Twilight Sparkle. I do not know by which chains your thoughts are bound."

Zecora stiffened, her lips pressed together, bound from protesting by Twilight's command.

Twilight turned to her, and hugged the other mare tightly. "I'm sorry Zecora, but I have to. Princess Luna is far too powerful, for either of us. If she wants to take me by force, she will, and then any chance of hiding this, if it isn't a trap, will be gone. Besides..." Twilight's fingers stroked Zecora's striped cheek tenderly. "I couldn't let you be hurt trying to defend me. You can speak and move. Just don't try to attack Luna."

"I... will obey. I can only hope the Princess will not lead you astray." Zecora hugged Twilight, painfully hard, then stepped back slowly.

Luna's eyes softened a little. "Thy loyalty does you credit, Zecora. I shall return thy owner, made whole in mind and memory, and you shall see that we are united in purpose." A flare of dark blue magic awoke about her slender horn. Zecora slumped bonelessly, falling limp into a cradle of energy and dangling unconscious as she was levitated onto the bed.

"Luna!" Twilight protested. "What did you do?"

"She shall sleep for some hours, now, as shall your devoted assistant. Come. Bring thy documents. The inhabitants of the town are stirring, and we must go."

Twilight hesitated again. What if something happened? She couldn't just leave her there...

Luna looked back at Twilight with a slight frown. "I understand thy hesitation. The sooner we leave, the sooner shall be thy return, with thy memories returned. Must I have you slumber also?"

She could probably fend off the first casting or two. She knew a few generalised counterspells, and one that might hold off sleep-based enchantments more efficiently. But then what? She didn't have any way to stop Luna wearing her down, which wouldn't take long, and then doing whatever she wished.

"No, I'll come," Twilight replied.

"Dress swiftly."

Twilight looked down at herself. She'd half forgotten she was in her dressing gown. "Um. Yes. Could you...?"

Luna gazed at Twilight for a long moment, then turned her back. Twilight hurried to pull clothes from her wardrobe and struggled into them, keeping one eye on Luna. After a couple of moments, she panted, "Done! I'm ready."

Luna nodded. While Twilight had dressed, she had folded her wings and rearranged her cloak over them. Now, when she pulled up her hood, she could have been any pony. It was simple, but effective enough. Together, they descended the stairs, and stepped out into the cool morning air. No pony was in sight.

Without wasting time or words, Luna turned her back on Ponyville and walked briskly in the direction of the town outskirts. Twilight had to hurry to keep up with the taller pony, half trotting every few steps to match her pace.

"Where are we going?" Twilight asked after a few moments.

"Not yet," Luna replied briefly, leaving Twilight frowning in frustration. Her satchel bounced at her hip, containing the cipher and the full notes and instructions for the charm. It wasn't lost on her that she was carrying an incredibly dangerous secret, with only the flimsiest protection.

"But-" she protested.

Luna quickened her pace, and Twilight had to break into a jog.

Well then. No more questions.

The last outlying houses fell behind them, and the two of them wound around a stand of tall trees, cloaking Ponyville from view. Luna slowed to a stop, and scanned the sky. "Twilight Sparkle, you must cling to me now."

Twilight blinked. Cling to the Princess? "...why?"

"Because now we shall fly." Luna shook her cloak, her wings pushing through the hidden slits to expand to their full span, and she looked down at Twilight expectantly.

Twilight opened her mouth to protest again, then closed it again. Further argument clearly wasn't going to get her anywhere. Besides...

Tentatively stepping closer, Twilight pressed her body tightly against Luna's, her head against the taller woman's chest. Her arms wound around Luna's waist, and the other mare's arms encircled her, drawing her closer.

Luna cast a final glance skyward and gestured with her horn. A shimmering distortion wrapped around them, the world outside altered as though seen through old, imperfect glass.

Twilight looked up at Luna with a surge of fascinated interest that almost overrode her anxious, shivery awareness that she was clasped tightly in the Princess's arms. "What was that? Is this a cloaking spell? Is this how you've been moving around unseen? How good is the camouflage? What does it look like from the outside?"

The look of single-minded focus on Luna's face eased, and a smile tugged at the corner of her lips. "I should have known that you would not let such a thing pass unremarked upon. It is a charm to hide that which should not be seen, as you surmise. It is not perfect, but it is hard to see against sky, or trees below."

"Will you teach me?" Twilight's eyes were shining.

Luna actually laughed once, and shook her head slightly. "Of course I shall, Twilight. Once this matter is concluded. Hold me tightly."

Luna's wings spread wider, and Twilight clung fiercely as instructed. The first heavy downbeat jerked them into the air, and Twilight felt a strange lightness spread through her as the Princess's magic eased the burden of her weight. The trees dropped away with dizzying speed, and through the bubble's strange refractions, Twilight saw the town of Ponyville spreading out like a map even as it fell behind.

Let's see. The sun was rising over there, so that was east, so they were heading... west by north west, more or less. There wasn't anything much on the ground in that direction, just forest and the Unicorn Range. There was Cloudsdale, but if she'd had to guess, she'd have said they were heading a little too far west to pass under it. So they were probably going somewhere isolated, unless Luna intended to fly them both all the way past the mountains and towards the city beyond.

There were two main possibilities. Either Luna had been conquered by the other - by Celestia, if the letter was telling even a little of the truth - or Luna was still serving past Twilight, and intended to restore her. If she was serving the other, it was possible that she was taking Twilight to her. In which case, she had only the duration of the flight to prepare. But prepare what?

The truth of it was that she didn't have a chance against her. She was a Princess. She moved the moon with her magic alone! The idea of opposing her was absurd, insane. Even moreso the idea of standing against Princess Celestia, which she would never want to do.

She was getting distracted. Okay. So fighting Luna was out. Maybe she could stun her, or confuse her... perhaps a powerful burst of light? Then she could flee into the forest. Better to be who knew where, endless miles from anypony that could help her, than to be remade by the other's wishes. She had the charm. She could work something out.

On the other hand, what if she believed everything she'd been told? Past Twilight had clearly taken some kind of precautions, ones that Luna had referenced, that kept her safe from the other. Her sister. What if Luna was being charmed against her will, and knew it? Maybe all of this was a kind of desperation, the only way she could think of to fight back.

Twilight sighed, her head resting against Luna's chest. She wouldn't, couldn't, abandon her to that. So either she absolutely had to run at the earliest opportunity, or absolutely couldn't.

Great.

Not to mention her growing suspicions that past Twilight herself was untrustworthy, twisted somehow...

Closing her eyes for a moment, Twilight concentrated on the cold air flowing past, letting it blow the tangled thoughts away. It rushed past her skin and ruffled her clothes with insistent fingers, as dark green forest washed past beneath them in the growing golden light of early morning. Princess Luna was fast. Even carrying her, which didn't seem to trouble the alicorn at all.

It was... pretty special, now that she took a moment to stop worrying, and just experience. The larger pony radiated warmth, holding off the chill of the thin autumn air, and Twilight's whole body tingled with pegasus magic, feeling as light as a feather. She'd seen the world like this from a balloon, spread out below in fantastic miniature detail, but flying in the arms of the Princess was a different experience altogether. No vast balloon creaking overhead, no wicker basket to hold onto. All the same, she felt safe. It didn't feel perilous at all. It was wonderful.

Maybe it was worth giving in to past Twilight, whatever she wanted, if it meant she could do more of this...

"Would it take you long to translate thy notes on the charm?"

Twilight started. She'd been so lost in her reverie, Luna's question took her completely by surprise. "Um, no, not too long. I'd begun decoding it when you arrived."

"That is good. It will be necessary soon."

Twilight's ears popped. They were losing height, she realised. There was a clearing opening up below, some sort of structure half lost among the trees at one edge. "Can you tell me what's happening? What's really happening?"

"Very well. From even before the moment you left to confront my sister, I was aware that I could not cast the charm, nor teach it to another, nor speak the words that activate the spell. You feared that I would be used against you, or find the charm itself too potent a temptation. I waited with terrible anxiety for your dreams the night that you were due to have challenged her. They were as I had feared. You had been purged of all your knowledge.

"I could not accept that. I believed that you would not be defeated so easily. I knew that the time would come when you would need another to cast a charm upon you. A unicorn untouched by my sister's manipulations. I came across one I believed had the potential to cast that charm, and brought her here. Here she has remained, for the previous two months, waiting to serve the purpose I have demanded of her."

The noise of the air rushing past grew louder as they swooped down towards the clearing, and even through the distorting shimmer of the spell that hid them, a wooden house was clearly visible nestling between two large oaks. "This pony agreed to wait until I found the charm again, when they didn't know how long it might be? If ever?"

"I did not offer her a choice," Luna replied with measured calm. Her wings swept wider, cupping the air, and the grass flattened beneath her as she settled to the ground.

Twilight slowly released her, stepping backwards in a daze. The cloaking spell resisted for an instant, then popped like a soap bubble. "You kidnapped somepony?" she asked, appalled.

Luna opened her mouth to reply, but was pre-empted by a demanding, imperious voice from the house.

"Princess Luna, is that you? I demand that you allow the Great and Powerful Trixie to leave this forsaken cabin at once! Or, or at least bring her some more supplies! The Great and Powerful Trixie is entirely out of cake. The only type left is the kind with walnuts, and you know that that doesn't count as cake at all. Are you listening?"

Twilight's jaw slowly dropped.

She looked at Luna.

Luna looked back at her gravely, then, after a moment, she shrugged.

"Walnuts, Princess Luna!" came the voice once again.

Twilight found that she was shaking her head in disbelief. "Trixie?" she hissed in an undertone.

"She hath the magical power required. I took her within days of my sister's triumph over you. I do not believe that there has been any opportunity for her to be interfered with."

"But you could have picked - almost anypony! Why her?"

"There are few other ponies that could have been kidnapped without being missed for several months." Luna shrugged again.

The cabin door burst open. Trixie stood dramatically framed by it, pointed magician's hat atop her head, cloak covered in stars thrown back over her shoulders, a two-toned outfit of dark and light purple beneath that incorporated a corset and a complex skirt cut shorter at the front than the back. Her gaze settled on Twilight.

"Wha- what are you doing here?" she protested, stepping forward, then wincing as the doorframe knocked her hat off. With a furious glare, designed to indicate to everypony that that hadn't happened, she levitated her hat back onto her head and tossed her snow-white mane. "Hah! I see! Now you, Twilight Sparkle, will be kept in this forsaken cabin in the woods, while I, the Great and Powerful Trixie, shall take your place in Ponyville!"

Twilight shook her head. "No."

Trixie drew back a step, looking affronted. "No? No? How dare you address the Great and Powerful Trixie in such a manner? Princess Luna!" Trixie drew herself up imperiously. "Punish her for her insolence."

Luna shook her head. "No."

"No? Again?! Trixie is offended! Trixie deserves far greater respect, far better treatment than these blunt negatives! Do you not know who she is?"

Twilight looked at Luna, and saw the same look on her face. She couldn't have stopped herself for a sack of bits and a diamond the size of an applecart.

"No," said Twilight and Luna together.

Trixie lifted her nose and snorted indignantly. "Hmph!" Spinning on her heel, she marched back into the cabin, remembering just in time to duck, and slammed the door.

Silence, for a few moments.

Luna stepped towards the cabin. "Come, Twilight Sparkle. You do not have time to waste. You must prepare the charm."

Twilight groaned, following her. "I'm placing my mind in the care of Trixie?"

"I shall stand at her side. If she speaks one word that is not as I direct, I shall deal with her severely."

Well, Twilight thought. That told her. She had to admit, she truly didn't want to see Princess Luna angry. She hadn't seen her lose her temper since she had been freed from the Nightmare, and she was in no hurry to repeat that experience.

She followed Luna into the cabin. It was comfortably appointed within, strewn with cushions and throws, and under most circumstances would have been a very pleasant place to stay. For someone like Trixie, with her constant need to show off, it must have been torture to be stranded in the middle of nowhere, without an audience.

"Please, make yourself comfortable in Trixie's home," said the other unicorn sulkily, sat in the corner with her arms folded, and staring out of the window. "Is there anything Trixie can get for you? She has hot and cold running trees, and a wide variety of entertainment, from listening to the swishing of leaves to watching moss growing on rocks."

Twilight pulled a face. Trixie really didn't deserve to be dumped out in the middle of nowhere, with nothing but - she scanned the room - a vast selection of books, and judging by the crumbs, a small mountain of cake to keep her company.

She found herself wondering about taking a holiday there herself, after everything was sorted out.

"I'm sorry that Princess Luna has been keeping you here against your will," Twilight said gently. "There's one thing that we need from you, and then you'll be free to go anywhere you want to."

Trixie snorted again. "The Great and Powerful Trixie isn't interested."

"I need you to learn a charm. A complicated, powerful charm, and I need you to learn it very, very fast. I'm not sure anypony else could do this." Twilight found, rather to her surprise, that she was at least partially telling the truth. Trixie might have an ego the size of a mountain and a narcissistic streak wide enough to build a second Canterlot on, but she truly did have a lot of magical potential.

Trixie glanced around from the window, peering out from under her hat brim. "A charm? What kind of charm?"

Now she had to be really careful. She couldn't lie to Trixie; she needed to understand the spell well enough to cast it. All the same, she didn't want to let her know just how potent it really was. "It's... a memory charm. Some of my memory is blocked, and I need somepony to cast the charm on me to release it."

"Ha! The Great and Powerful Trixie sees no need to help you. She rather enjoys this cabin." She looked back out of the window.

Luna took a step forward, but Twilight held up a hand and shook her head. Oh, she didn't want to say this... "Nopony else can do this. I humbly ask for the Great and Powerful Trixie's help."

Trixie turned around and stood up, lifting her head and looking down at Twilight condescendingly. "So tragic. The Great and Powerful Trixie will help you with your little problem."

Twilight gritted her teeth and smiled as best she could under the circumstances. "I need a few minutes to decode my notes. I'll give you the instructions as soon as I'm ready."

"Work swiftly, Twilight! The Great and Powerful Trixie's time is precious," she replied grandly. "Princess Luna? Kindly bring Trixie something to eat."

Twilight gaped as Luna went off to fetch something, then shook her head and sat down at the cabin's single small table. Spreading the sheet out in front of her, she took her sealed ink bottle from her satchel and began to write.

She was uncomfortably aware of Trixie trying to read over her shoulder, while pretending not to be interested. She hunched over the parchment a little more. So this was it. It was time to either lose all her memories (but if this was a trap, it was implausibly complex) or regain everything past Twilight knew. But even after everything, even though Luna was hardly giving her a choice, she wasn't sure that she wanted all of those memories. She was afraid of what might come with them.

She had past Twilight's instructions for recovering her memory, and a stern warning not to change them in any way. It was clearly very important to her former self that she have her memories returned all at once. What if she didn't go along with that plan?

Folding the top of the parchment over the completed charm, she fished out the original memory recovery instructions past Twilight had written for her.

'All commands given to you are ended. All blocks placed on your memory are removed. Any changes to your perceptions are undone. You will remember everything that the charm has blocked or removed, including periods spent in the charm trance. Slumber.

It was straightforward, and very simple. That was good. But it didn't give her any way to know what she was getting herself into until it was too late. If past Twilight was really hiding things from her, than that was by design.

She couldn't trust them. What she needed was a set of instructions with some safeguards.

Twilight bent over the parchment and began to write, her face set in a frown of concentration. She was caught between purging all memory blocks that the other had left within her, and risking exposing herself to whatever taint might have corrupted her morals before.

These instructions were going to be pressed into her mind. She had to be absolutely sure she got this right.

After a few moments, she became aware that Luna was at her side once more. "Are you finished, Twilight Sparkle?"

"...yes." Twilight laid down her quill and went over the words she'd written once again, checking a final time for contradictions or inconsistencies.

Luna frowned slightly as she read the parchment. "This does not guarantee you will choose to take back your memories, Twilight. Why have you written this?"

Twilight looked up at her, her expression resolute. "I need to know that I'm giving myself a choice. I know you could stop Trixie reading this, and change my instructions when it's too late for me to protest. I'm asking you not to. Let me come to terms with what I remember."

Luna's frown deepened, and she looked away. "You ask for much." After a moment, she sighed, and hung her head. "Very well, Twilight. I shall abide by thy wishes."

Twilight stood up, and somewhat to her own surprise, squeezed Luna's hand tightly in both of hers. "It's going to be okay. I promise."

Luna's shoulders slumped slightly, and Twilight felt a little tremor run through her. Looking up into the Princess's eyes, all of a sudden she saw the heartache behind her firm manner, just as intent as that desperation she'd seen written across Zecora's face.

"Thank you, Twilight," Luna replied quietly.

Twilight stepped back, and looked over at Trixie, who was eating a cupcake and pointedly paying no attention to their conversation. "Trixie? The charm is ready."

"It's about time! The Great and Powerful Trixie doesn't have all day, you know. She is far too important to have her time wasted." Finishing off her cupcake, she stood up and moved to take the parchment.

Luna's wing snapped out, blocking her. The Princess turned towards Trixie and gazed down at her, eyes hard. "Know this, Trixie Lulamoon. Once you hath read the charm, you shall not seek to cast it upon Twilight until I give my assent. You shall not speak a single word, other than those I direct. If you seek to violate these terms, I shall punish you severely. Have I made myself clear?"

Trixie's eyes widened, and for a moment there was naked fear on her face before she drew herself up to meet Luna's gaze and tossed her mane casually. "The Great and Powerful Trixie isn't a foal, Princess Luna. Make room for her to read this charm. Shoo."

Luna slowly folded her wing, letting Trixie pass, and Twilight slid the decoded parchment across the table. Trixie frowned, muttering to herself as she read the charm's movements and directions for managing the flow of her magic.

Twilight coughed. "Um. I should probably find a seat or something, in case I collapse when it's cast."

"You shall not, Twilight. Nonetheless." Luna nodded towards a comfortable-looking blue armchair, not taking her eyes off Trixie.

Twilight crossed the room slowly, settling into the chair's depths and gripping its gently frayed arms. The dead quiet had begun to take on an ominous feel. She couldn't help the churn of anxiousness in her stomach, knowing that any second her mind was going to be opened wide by powerful magic. She might not be the same person in a moment that she was now. The urge to flee was tangible.

Trixie looked up from the parchment and opened her mouth.

"Not a word," Luna interrupted at once, in iron tones. "Are you prepared to cast the charm upon Twilight?"

Trixie caught her lip between her teeth, then nodded slowly.

"Do you understand that you are to perform the charm, then read the words at the bottom of the parchment aloud? That you shall then be utterly silent until given permission to speak?"

A flash of irritation crossed Trixie's face, and she nodded again, folding her arms indignantly, before she walked over to face Twilight.

"Begin."

This was it. Twilight's fingers dug into the chair's padding. Trixie kept her eyes glued to the parchment, held aloft in one hand, as she swept her horn through a sequence of movements.

Nothing happened.

A flush of angry embarrassment flooded Trixie's powder-blue cheeks, and she executed the pattern again. A third time. A fourth. Visibly becoming frustrated, Trixie glanced back at Luna, about to protest aloud, then plainly thought better of it. Clutching the parchment in both hands, slightly crumpling it, she focused on the words again.

Minutes ticked past in dead silence. Twilight found she was teasing white stuffing out of the armchair through a little hole in the covering and desisted, trying to remain calm. Luna's face was unreadable, but Twilight had no doubt that the Princess was simmering with her own mixture of frustration and desperation.

Eventually, Trixie looked up from the parchment, and focused squarely on Twilight. Without glancing at the instructions, her horn swept in a delicate, intricate pattern, her hands mimicking the movements, and a gossamer shimmer flickered from the very tip to strike Twilight squarely.

Twilight blinked. Had something just happened? "Did it work?" she asked, looking up at Princess Luna.

"Trixie, you shall speak the first word that Twilight hath written, now."

Trixie nodded, flushed and triumphant, a wide smile on her lips. Her mouth moved-

Twilight was sitting in a different chair. She was home, in the familiar confines of her own library, sat facing an oval table. Along its polished length were an array of glowing cubes of different colours, each marked with symbols and familiar cutiemarks.

In the chair opposite her sat Twilight Sparkle.

The other Twilight frowned. "I see. I should have expected this."

"You were hiding things from me. I couldn't risk turning into you without knowing what I'd become, first," Twilight replied. "I will assess each memory that's been hidden from me, and when I'm finished, I'll decide which memories to keep."

The two gazed at each other. The other Twilight, past Twilight, didn't look strange, or twisted. As hard as she tried to see a sign of corruption, there was nothing to see.

Twilight's former self smiled after a moment. "Princess Luna got Trixie to cast the charm on me? She's wonderful. I couldn't risk giving Luna any role in my contingency plans in case Celestia took her over, and she did this all by herself." She shook her head, fondness and pride in her voice.

"So you still claim Celestia took my memory away?" Twilight asked.

"Yes." The other Twilight sobered at once. "The memories are here that prove it." She gestured along the row of glowing cubes. The last few shone with white light, each marked by a sunburst insignia.

Twilight bit her lip. There could be no lies here. It had to be true.

She really hadn't wanted it to be true.

"Where do we start?" she asked after a moment.

Her doppelganger picked up the first cube of the row. It glowed with a dim orange light, and Applejack's cutiemark was emblazoned on the side. "The walls that blocked you from even thinking about all this are gone now. If you're ready to begin remembering, you'd better start at the beginning. I need you to understand."

It was strange to look into her own pleading face and wonder if she could be trusted. Twilight reached out, and took hold of the cube.

A flickering flash of memories rocked her. The finding of the charm, the first casting. The arousal, the guilt, the shame, the lust. Applejack submitting to her. Blocking Applejack's memories, so she could use her more easily without worrying about consequences.

Twilight let go of the cube with a gasp. It had only been an instant, but the flood of memory had set her heart pounding. "You were wiping Applejack's mind! You were using magic to force her to do things and making her forget! That's exactly what you said was so terrible about the other!"

The other Twilight looked aside, guilt plain on her face. "I... yes. I didn't know what to do. I couldn't remove the charm, and I was just so tempted by it. It felt like I wasn't doing any harm."

"It's horrible! Knowing you've been changed, feeling the way your thoughts keep being blocked. You did that to Applejack!"

"I know. I remember everything you remember. I know how hard it's been for you, since Celestia took away everything. But I remember it! All of it! Everything she's done, and what she will do. Twilight, please, you have to keep looking. We can't stop now."

Twilight folded her arms. "I'll look. But if I'm not convinced, if I choose to stop, then everything I don't keep goes away. I'm really beginning to think that Celestia did the right thing when she took this charm away from you."

She picked up the second cube, shining with soft white light, and marked with Rarity's cutiemark. Instantly, she was being caught! She had to do something! Rarity's arms falling to her sides, whispering against her dress. Making her believe everything was normal, and being surprised when she made the outfit - the one in the wardrobe! - for Applejack. Sex, sex with Applejack, in front of Rarity, oh, the lust, and Rarity coming to her after, asking to be hers, ready to serve, eager to...

The cube dropped from Twilight's fingers as her grip loosened. Her heart was pounding again, and she was horrified to find that her body was alight with arousal. Each package of memories didn't just include the central memory linked to one of her friends, but came with all sorts of associated pieces, stray thoughts about them she'd been made to forget, secretive kisses, the vivid fantasies she'd masturbated to in her bed. It was overwhelming. It felt so good to have Rarity surrender to her, to see Applejack dressed up in her fetish outfit, to remember her tongue...

It was so easy to slip into thinking the way she had at the time, lustful, losing herself to the power she held. Twilight held on grimly to her quivering morality.

"You... you charmed Rarity! You made her think everything was fine, and then you just accepted her when your own half-assed instructions brought her back to you as a... as a servant! You knew she wasn't in her right mind!"

The other Twilight hunched her shoulders under the barrage of criticism, and said nothing.

"This isn't going well. I was right to think you had been tainted by this charm." Twilight revelled in her ability to hang onto her sense of right and wrong, and giddy with her sense of accomplishment, she seized the next cube. A dozen different images of Rainbow Dash snapped into existence in her mind, naked and eager. Terrifyingly eager. She'd actually asked Rainbow's consent... even if it had been something she'd pressured Rainbow to accept without fully explaining. That made it alright, didn't it?

The pegasus had been incredible.

Twilight's eyes squeezed shut as she tried to push back the tide of memories. The more she tried to focus on what had happened, the manipulation she'd carried out, the incredibly unethical brainwashing she'd plainly been becoming addicted to, the more the scenes of sexual ecstasy came back instead, bypassing her morals and speaking directly to her body in a language of heat and remembered touches. Applejack. Rainbow. Rarity. All three of them together, oh Celestia, yes...

No! Her eyes flashed open. The other Twilight was watching her intensely, and after a moment, she spoke softly. "I know it looks bad, some of the things we did. But it made us happy. Not just you and I, but all of us."

"It wasn't right, Twilight! We made them feel happy, we wouldn't let them feel anything else!"

"No, we didn't." The pony she thought of as past Twilight shook her head. "Think about what happened to Rarity. Really think. We made her think that it was acceptable for us to be enchanting Applejack, and that wasn't right, I admit it, but I thought it was better than hiding her memories as well. I never told her to love me! I didn't tell her to want to be with me, and when she came to me and said that she was tired of being hurt in love, of loving the wrong people, she was sincere! You know what I felt. I wanted to look after her, to give her the affection she wanted."

"You have no idea how many of her memories were rewritten to make her think that!" Twilight retorted, though the sharpness in her voice had diminished a little.

"Applejack has been fantasising about being someone's sextoy all along, I never made her want that. Isn't it better that it's us, rather than some colt who might take advantage of her?" The other Twilight winced at Twilight's expression, and added hastily, "Take advantage to hurt her, I mean. Applejack is getting everything she ever wanted. Rarity is getting all the love she needs, and we didn't make either of them want that. Rainbow loves Applejack, and us, and without the charm she'd never have either of us, let alone both together. Don't you think she thinks it's worth it?"

"It isn't right," murmured Twilight, but she shook her head and picked up the next cube, a smaller one, again marked with Applejack's symbol. Instantly, she was engulfed with her past self's worry for Applejack's safety, determined to change things so that she could refuse orders if they'd upset her, but all the same absolutely rejecting the idea of ever letting her go. She had to be happy. She had to be hers. She had to fuck her and kiss her and never, ever let her go...!

Love. It was a terrifying, possessive kind of love that she was clear-headed enough to see might do terrible damage, but it was love, undeniable.

"I didn't want Applejack to get hurt, or to hurt anyone. I was giving them choices! I was giving them ways out! She chose this!"

For a moment, she thought the words were her own thoughts, but no. They were spoken by the other Twilight. She looked scared, and slightly desperate.

A strange surge of pity for her other self touched her heart. "You... we... love her very much, don't we," Twilight said softly.

The other Twilight nodded slowly. "Yes. She loved us. It's not fair that it's all been taken away. I would have done anything... I did do everything I could to protect her from being taken away."

"But who was protecting her from you?" Twilight asked the question gently, remorselessly. Her duplicate looked stricken, and Twilight sighed as she reached out for the next in the row, a pale yellow cube with Fluttershy's mark. Instantly she was overwhelmed with sensations, as an impossibly arousing scene flicked before her. For a moment she felt Rainbow's mindless tongue on her sex, was watching a bare-chested Fluttershy sitting on Rarity's face without the slightest notion anything was wrong, watching her scamper nude about the room, giving in to Twilight's promises to make her loved, and cared for...

Her hands gripped the arms of the chair hard enough to make the underlying wood frame groan in protest. She looked at the floor, panting, unable to meet the other Twilight's eyes as shivers raced through her. She had been depraved! Using her friends like toys, using them as furniture for goodness sakes!

She looked up, all the pity and sympathy for her past self driven away by the sheer struggle to contain the twisted lust, the remembered orgasms, the intensity of her desire for more. Her voice still unsteady, she said raggedly, "I see. So what Applejack, Rarity and Rainbow all secretly wanted was to be turned into interior decoration?"

Again, her double winced. "You did hear them when it was over. They were disappointed I hadn't let them experience it all at the time, not upset, or traumatised. It was just... a game."

"Do you really think that any of them would have agreed to that if they'd been in their right minds?" Twilight demanded. Though now she thought about it, Applejack might have. Maybe even Rainbow too.

"Applejack might have gone along with it. If Rainbow could have gotten over not being the centre of attention, maybe her too," the other Twilight offered.

Twilight didn't reply. Their thoughts were too similar; the imaginary copy of herself knew everything both of them knew, and all the hidden memories that had been locked away by Celestia as well. She was at a distinct disadvantage trying to argue with her.

Why did the memory of her using her friends turn her on so much? It was shameful! It was unfair! It was an insult to the ponies that she loved so much to play with them without regard for their feelings. Except she'd tried to make sure they could disobey. Except she had given them a choice to give in to her. But she hadn't, she'd rigged the odds, made it almost impossible for them to say no... it was too much!

Twilight covered her face with her hands, and tried to focus on something other than the maelstrom of emotion and temptation raging inside her.

"Luna caught us."

She looked up into the face of the other. "What?"

"She caught us. She saw it in our dreams. So we charmed her, in her dreams. It was the only way to protect everypony, she was going to take Applejack and everyone away, she was going to strip us of our magic..."

Impossible. Luna wouldn't do such a thing. Past Twilight couldn't have taken her by force. Madness, sheer madness!

Twilight lunged for the next cube, deep blue and marked with a solitary moon symbol that shed a white light of its own. Dreams and reality blurred through her mind, one chasing the other as she saw Luna advancing on her, felt fear and desperation great enough to crack the world. Luna's shock as the spell actually worked in her own realm of unreality, the Princess at her door, Luna nude, Luna thoughtlessly sucking on a shaft that wasn't there, but had once been attached to Celestia-

"I don't believe it!" she gasped aloud as the memories released their grip. "I won't! I can't! Celestia would never! This is... this is a trick!"

"No, it isn't. I understand now, why it worked. It really happened, all of it." The Twilight of the past leaned forward and rested her warm hand on Twilight's own. "I'm sorry, I'm so sorry, to do this to you. I know what you're feeling. I felt it too. But it is true. She can't be trusted, not with the charm. No more than we can."

Twilight shook her head dazedly. "You - you're confessing that I shouldn't have this power! You just said we can't be trusted!"

"Not... completely. I'm sorry, Twilight, I'm really sorry, but... you need to see this." The image of her past self, of the self she would be if she accepted the memories entirely, drew back. Her hand rested lightly on a grey-striped cube, glowing with dim golden light.

It had to be Zecora's. Twilight hesitated. She remembered now. Luna had told her that Pinkie suspected her, that Zecora had suspected. But that was why she'd offered herself, wasn't it? She wanted to be controlled. She needed to understand what had made Zecora into the woman she'd become. Loving, playful, and utterly devoted. Her hand slid over the embossed spiral mark.

Dreams, she was in a dream, it was strange and beautiful, but she had a plan, this was a test, and it... worked. Zecora naked. Zecora mindless. Zecora with her mouth between Twilight's legs, her mind rewritten, her beliefs changed to make her believe it had been her idea all along.

"No!" she blurted out, desperately thrusting aside the treacherous voice getting ever stronger that understood, that loved everything she'd seen, that wanted more, and more, and more. "You - you lied to her! You lied to me! You made me think she had come to us of her own choice, but it was all you!"

Opposite her, Twilight wrapped her arms tightly around herself, staring off to one side. Her voice tense, she replied very quietly, "She had found out. She could have-"

"You could have made her forget!"

"I didn't want to make her forget, I wanted to let her be part of-"

"You didn't let her do anything!" Twilight's face was flushed with anger, all the more enraged by the guilt she felt herself.

"You can let her go! You can give her the choice that I gave Applejack, and Rarity, and all the others," Twilight's other self pleaded.

"I'm going to have to. I have to remember this, so I know what I have to undo. But I'm really not happy! Do you understand I can't trust you? I can't trust myself! What happened to me, to turn me into you?"

It was hard to see the other Twilight flinch, as though slapped, even if a part of her was angry enough to want to keep shouting at her.

"I was afraid you wouldn't let yourself remember. Not if you knew the whole truth. It's... too much, to take in all at once," the other pony replied quietly. "I do feel guilty over what I've done. But... please. Remember the bed, the morning the three of us woke up together? Luna's face? She was lonely, she was aching with loneliness.

"She'd resigned herself to waiting out the life of every pony alive, and maybe their foals, and their foals, just to find someone that wasn't afraid of her. She wants to love you, Twilight. What about Zecora? Shunned, feared by Ponyville? Even now, ponies are still a little scared of her. She has acceptance, and love, and warmth!

"You can give them choices, to stay with you or not. You can make them happy. Everyone you love, you can make happy, and all it takes to make it possible is the charm. No jealousy, no bitterness, just... everyone loving and living together. It really was the best time of my whole life. You can feel that. Stop worrying about what happened when we had sex, and think about the rest of the time. Weren't you happy? Don't you think the others would want that too?"

Twilight closed her eyes. "Wait, please. I need to think."

"Of course. As long as you need."

Okay. Accept that she could offer Zecora and Luna their freedom the moment she awoke from her reverie - she had to, so she'd have to remember at least enough to know that the two weren't voluntarily under her control. Could she really accept all she'd done? She knew that past Twilight had pledged to herself to offer their freedom to everyone she'd charmed, but she hadn't, and she wasn't sure she'd ever been going to.

The trouble was, even remembering what she'd done was enough to tempt her. Horribly. She was avoiding remembering everything she'd just seen, but she couldn't entirely push it away. The emotion, the desire, shuddered beneath the surface of her self control like a volcano beneath a glacier.

Put that aside too. Was she right? What if the charm was the only way to make her friends that happy? There was a togetherness, a special love that she didn't believe would have come about any other way. For one thing, Applejack and Rarity weren't even attracted to mares, and goodness knew about Zecora and Luna. She'd never even asked. Wasn't it true that she could make things better? She could release the ponies that wanted their freedom, and the rest of them could stay together.

She was shakily aware that the thoughts she was having were ones she wouldn't have had, if she didn't hold the memories of seducing almost all her friends within her. Maybe she should end the reverie, reject everything, and remain the pony she had been before she'd ever found out about the charm.

But she had to remember the truth about Zecora. The truth about Luna. And she still didn't know what Celestia had really done to her.

She couldn't stop yet.

"I'm ready for the next one," she said finally.

The other pony looked up quickly, and slid a bubblegum pink cube across the table. Her lips parted to speak, but she seemed to think better of it and subsided awkwardly.

Twilight took a deep breath, and picked up the cube. Again, memory flowed into her, a streamer of experiences and moments. Pinkie naked. Pinkie giggling. Rolling around with her as they play-fought, licking the other pony's sweet-tasting body, trying out the head to tail position as they licked each other. For the first time, she surfaced from the memory with a giggle on her lips. "Oh, Pinkie," she murmured fondly, as she set down the cube again.

"Gruff Gruffington the Tea Drinking Stranger," the other Twilight agreed.

"She knew what you were doing, and she agreed anyway. You Pinkie promised to be good!" Twilight added abruptly, pointing an accusing finger.

"I was! I didn't charm anyone else." An awkward look spread across the other mare's face, before she added hesitantly, "Well, one other pony. But there were circumstances. I didn't keep them."

Twilight gave her a long look, and picked up another Luna-cube. Instantly, a wash of anxiety broke over her. Writing the now-familiar messages, trying to shape them to guide herself, to give herself the best possible chance to remember. Luna, arriving in response to a summons in Twilight's dreams. Luna, learning the charm herself, then as a blank-eyed automaton, casting it upon Twilight.

The memory was dark now, blind to everything except Luna's face, and her voice, speaking the Truth. If Twilight was ever charmed again, she would immediately forget all memories related to Incident 'A'. Past Twilight understood, knew that her contingency plans were what the words meant, and present Twilight understood that Luna wasn't meant to know what she was commanding Twilight to do, even if Celestia dug out the memories from her.

The darkness in her memory passed, the world returned, and she finished instructing Luna to forget the details of the charm, to never cast the charm again even if she was shown it, never to speak the words, never to teach another. As many layers of defence as she could think of, hoping that one might hold if Luna was converted carelessly when Celestia finally discovered the truth.

She shivered as she laid down the cube on the table. "But she never did."

"I don't think so. She would never have allowed Luna to do this if she had."

Twilight gazed at the cubes. The remaining ones were almost all glowing white, but there was one more rainbow-hued cube, a different cutie mark on each face. That had to be more memories of things she'd done with her friends. More lust. More sex. More depravity.

Her thighs squeezed together as she reached out to touch it.

Fluttershy bounding naked across the floor, each mare dressed in a different fetish outfit, the bed, the strap on, fucking them fucking them all, one after another, making Rainbow cry out, Rarity, Pinkie, Fluttershy, Applejack, making them fuck each other, a never-ending flickering slideshow of sex, and pleasure and domination and power and cumming, cumming-!

Twilight trembled violently as the cube spilled from her fingers, snapping back to awareness of her body too late to stop herself. She arched violently against the chair, a cry fighting its way out as all the simmering lust in her body finally consumed her. She lay dazed for a moment, breathing heavily, before she abruptly came to her senses and jerked into a sitting position, hugging her arms around her knees.

The other Twilight was looking at her with a heat in her eyes that she was unable to hide, and she murmured after a moment, "I never thought I'd find that so hot."

Twilight blushed heavily, a wave of embarrassment crashing over her as the lust ebbed away. Even if the other pony was only a construct of her imagination and memory, it was still hard not to feel sheepish about what she'd just done.

"S-so," she tried, "I - I remember everything up to when we were about to go to Canterlot. Is this... where we lose?"

"Yes." Her double gazed at her, growing serious. "She tricked us. She wiped our memories. But she talked to us first. You have to keep this memory. It's the key. Take it. Take your time with it. You need to see it clearly."

Twilight nodded once, her eyes on the softly glowing sunburst cubes, and reached out to touch the first. Memory surged, almost tangibly, and she submerged herself in the stream. Train. Canterlot. Castle. Guards, nobles, vault, what she'd done to Pure Heart, the Elements, the throne room, Celestia, charming her, the horrible realisation as-

"Awaken, Twilight." said Princess Celestia.

There was no time to think, barely time to hear. The world vanished. The only thing that mattered was Celestia. Only her face. Only her voice.

She filled Twilight's world.

Twilight felt her lips move, shaping the words 'I am awakened,' but she couldn't hear the words she said. It didn't matter. There was no concept of anything but listening, and gazing.

"Oh, Twilight. I wish you hadn't done this," came the divine Voice. She could have listened to it forever. Celestia buried her face in her hands, eclipsing Twilight's view, but she waited with timeless patience, and eventually Celestia lifted her head once more.

"Are your friends here?"

'Yes, they are outside the doors.' she mouthed, thoughtless joy filling her empty world at being able to reply.

"Have you used the charm on them?"

'Yes, all of them.' Joy. Silence. Waiting for the Voice. She watched, focused intently on Celestia's face, as the elder pony closed her eyes tightly.

"I've released the door. You will open it, and recite: 'Awaken. Act normally, stay here, and wait for further instructions.' Then you will speak the command to end their trance, close the door and return to me. Can you remember that, Twilight?"

'Yes, Princess. I will open the door, speak, and close it, then come back to you.'

Joy. Purpose. She was the thing that would open the door, speak, and close the door. It swam into the centre of her vision, two double doors in a deeper darkness, and slowly grew as she drifted towards it.

The door opened under her hand. She spoke into a blank void, hearing nothing, seeing nothing that mattered. The door closed.

Celestia filled her vision once again, looking tired. Twilight waited with blank, formless anticipation as Her lips parted again.

"You will stop fighting, and stay completely calm. You won't try to leave the room. You will speak only the truth."

Yes. The words were Perfect Truth. 'I will be completely calm, won't try to leave, and I'll speak only the truth.'

"Slumber."

The memory of the Voice vanished. She was stood before Celestia - a very awake and aware Celestia - and she knew that she couldn't lie in her presence. Had never been able to. Standing before Celestia, she could only speak the truth. She knew that she had lost, that further fighting was futile.

She was perfectly calm, an ice cold clarity that felt like a cold breeze through her mind.

She'd tried to charm Celestia, but it hadn't worked. Celestia had cast it on her in return, but now she was just standing there, looking tired and sad. She didn't remember being charmed, but that meant nothing. Looking around for her ear muffs, with mere academic interest, she asked in conversational tones, "Have I been charmed yet, Princess?"

Celestia looked down at her with deep unhappiness, and replied softly, "Yes, Twilight. I have charmed you. You will not leave, panic, or lie."

Twilight nodded. Celestia had no reason to lie; she had lost, and Celestia now controlled her mind. A quiet sadness spread through her as she thought of her friends, so near and so far, on the other side of the sealed door. Her gaze fell to the floor, and she shook her head once.

"I'm so sorry, Princess. For everything. I really didn't want to do this, even if it turned me on to think about controlling you." A little tremor of distant surprise tingled at the edge of her thoughts. She hadn't meant to say so much. She looked up at Celestia again.

The Princess was gazing at Twilight, her expression an almost perfect mask. Only a pony that was as familiar with her moods as Twilight herself could have seen the shock that she failed to completely camouflage.

She had nothing left to lose. "Princess - please don't charm me again. I wouldn't want to lose my memories of everything that's happened," she asked politely. It should have been a plea, desperate, urgent, but those emotions couldn't thrive in the chill calm wrapped around her thoughts.

Celestia shook her head once, half turning away. "I'm sorry, Twilight. I am truly sorry, but I must. This charm should never have come into your possession. If only I'd known. Did you discover it from a book?"

"Yes," Twilight replied. She was about to add that it came from a book called 'Peaceful Charms', but on impulse decided to try staying silent. No impulse overrode her will; she said nothing more.

Interesting.

"Did it come from my former home, the Castle of Two Sisters?"

"Yes." From the library, she thought, but again did not say. So she didn't have to volunteer information. Did she have to answer Celestia's questions at all? Probably not. But if she refused to answer, she'd be altered so that she had to answer.

Celestia had said she couldn't lie. When she'd said that she hadn't wanted to charm Celestia, she immediately had to confess that she'd fantasised about controlling her, because without that, it wouldn't have been a true statement. But all the same, she didn't have to answer questions. If she said something that was true after one was asked, and Celestia assumed it was an answer to her question... that still wasn't lying.

Celestia sighed. "I had suspected as much. It has slumbered there for many years."

"Was it your spellbook?" Twilight asked politely. She couldn't fight. She could, however, mislead. Her own sadness, her guilt, were present but held at arm's length. What could she accomplish, now that she had lost?

Celestia turned around and looked at her couch, driven clean across the room by the pounding of Twilight's magic. She shook her head slightly, levitating it in a golden haze, and it drifted gently but unstoppably through the air back to its rightful place. The scratch marks it had left across the floor, however, remained.

The regal alicorn sat, her mane billowing about her. Something of grief, even shame, was in her expression, and it looked foreign and lost there. "Yes, Twilight. It was my own."

"Why did you have such a spell? I found it hard to believe that it was yours."

She looked away, then sighed again, deeply. "Come and sit with me, Twilight."

There was no compulsion to comply. Useful.

Twilight crossed the floor, settling down beside her estranged mentor, and looked up at her. The single pony she admired most in all the world. Twilight had tried to overthrow her. Celestia had brainwashed her sister. Both of them knew each other's betrayals, now.

Both were tarnished.

Not meeting Twilight's eyes, Celestia began to speak. "I fear you will find me lacking, Twilight. It is hard to speak of it, but you deserve an answer, and I wish to tell you. I wish to tell at least somepony, before I seal away your memories of all that has happened, and bury my mistakes with them. I cannot express how hard it was to see your anger and fear as you struck at me, all because of my own carelessness."

Guilt scraped blunted claws against Twilight's preternatural calm, and failed to find purchase.

Celestia shook her head slightly. "It began with Luna, long, long ago. We lived in the Castle of Two Sisters, and reigned over ponykind together, the day and the night. I was gloriously happy. It took a long time for me to notice that she had been slowly becoming... different. Angrier. More selfish, and arrogant. I tried to talk to her. I tried everything I could think of to reach out to her. But the more I tried, the more she sealed her emotions away from me.

"I feared that if she continued to abandon herself to her jealousy and pride, it would become impossible to mend the rift that was growing between us. We were barely on speaking terms, and for the first time, I began to wonder whether we might part ways. I became... frustrated, and desperate." She spoke quietly, her soft voice carrying through the empty audience chamber. Her mane drifted around her face, as if seeking to cloak her from Twilight's quiet, attentive gaze.

"When I had exhausted every option I could conceive of, I began to seek spells that might purge corruption. I had hoped that whatever darkness grew in her could be removed. She could be my loving sister again. I discovered many things thought lost to time; I have been a scholar as well, Twilight. I found lore, ancient by even the standards of Luna and I, that hinted at the power to reshape minds and memories.

"I sought it out. From those scraps of long-ago incantations, I created the charm that you know. It had to be powerful, powerful enough to affect my sister and tuned to her very essence, the essence of dreams. I only meant to use it for healing."

Celestia's milk-white throat bobbed as she swallowed. The words seemed to be coming with more and more effort. "Tell me, Twilight. Have you used the charm in ways you would have found unethical, before it came into your possession?"

"Yes, I have. I didn't mean to at first, but it just got more and more out of hand." Twilight felt a strange, dim sympathy for Celestia. She knew the way that a pony could, moment by moment, lose her self control. "It was always too easy."

"As it was with you, so it was with me. I used the spell upon Luna, my beloved sister, and I drained her bitterness, her envy, and her anger. She once more became the sister I had missed so badly. I was filled with joy." Celestia shook her head. "If I had ended it there, then I would have averted a great deal of heartbreak. But I did not. I found myself thinking about it. Over time, as months passed, I found smaller and smaller excuses to use it. Small disagreements were prompts to enthral her, to make certain that she would not fall back into her bad habits.

"Then, I began to use it simply to watch her move around our castle, enjoying her inability to perceive my presence. After that, I began to... touch her." Celestia's voice broke, and she went silent for a long moment. "It became clear to me that I could not be trusted with the spell. In a moment of strength of will, I summoned Luna and freed her from the changes I had imposed on her. I could not risk leaving them in place, not without supervision of the charm's effects. Then I used a dear friend, a unicorn of great power, to use that power upon me and command that I forget the charm. Their task done, they forgot, and so did I. I had undone my mistake as though it had never been. Almost.

"The only surviving knowledge of the charm lay in a book I had set aside for safekeeping, in a forbidden part of the library. I could not bring myself to destroy it entirely; it had been too painstaking to create, and I thought I might one day have need of it. I set one single condition that would unlock my memories of it. Do you know what it was, Twilight?"

Even through her cold calm, Twilight felt a distant wave of despair. "If anyone ever sought to cast the charm upon you. You had no idea it existed until I tried to fight you with it. I saw something happen to you, and I thought the charm was fighting to control you, but I was wrong. You were remembering."

"Yes. In coming here, in casting the charm upon me, you awakened my memory of those dark days. Now I know what I did not know then; that with the charm's influence removed, Luna returned to her dark path. She became infested with shadow, or perhaps had been all along, kept quiescent by the spell's power. We fought. I did not know that there was another way. I had never dreamed when I sealed away the charm that I might one day banish her for the lack of it."

It was... wrong, to see Celestia like this. She was always calm, unruffled, gently playful. To see her unhappiness, her distress, was like seeing a mountain fall to pieces before Twilight's eyes. There was a soft, distant ache of sadness about the thought, as though she were losing something important.

"I left the castle. Another choice I had not foreseen. The book remained behind, through these many years, preserved until I had need of it. Now you have found it, and found the same temptations too strong."

Twilight suddenly found there was a question she needed to ask. "Is it the spell that changes the pony using it? Or is it just... power?"

"I wish that I knew. There are elements of old magic to it, that much is true. There could be some corruptive element, well hidden, an ancient trap that I was not wise enough to avoid. Or it may simply be that anypony given such power over the hearts and minds of those around them finally finds their morals insufficient to prevent them from using it." Celestia ran her finger along the edge of a crimson cushion, seemingly absorbed in the simple motion. "I would prefer to believe that it is darkness from without, than within myself. But I do not know for certain. If a pony like you has been tainted by it, then perhaps it truly was the charm itself, all along."

So many answers, just as she was about to lose them all. What else did she need to know? "I'm sorry to ask, but- why didn't it work?" Twilight asked. A slight frown touched her features. "I was certain that it had struck you."

Celestia smiled wryly. "It was too potent a piece of magic to leave without precautions. As much as it was made to conquer my sister, it was made to be futile against myself. No casting of it, no matter how powerful, could touch me."

Twilight's frown deepened. But that meant...

"Now, Twilight," said Celestia quietly and inexorably, "It's time for you to answer my questions. Why did you think I was using the charm?"

"I believed the spellbook belonged to you. I believed you had created the charm. Once I knew you had it, it never occurred to me that you might not be using it." Twilight said. All of those statements were true.

"I understand." Celestia hesitated, then said in a softer tone, "Why did you try to charm me, Twilight? Were you going to control me? What could have made you turn on me like this?"

"I was afraid that you'd find out I'd been using the charm, and take away the ponies I'd charmed. I was happy. I didn't want to be controlled, or have it all taken away." Twilight paused, then added matter-of-factly, "I was arguing with myself over controlling you, or just stopping you using the charm. I had started vividly fantasising about you, between the bouts of guilt."

Celestia blinked, her head drawing back a little. She was silent for a moment, before she asked, "Who have you charmed, Twilight?"

"I've charmed Applejack, Rarity, Rainbow Dash, Fluttershy and Pinkie Pie in Ponyville, and I had to charm Pure Heart the vault guard here in Canterlot to gain access to the Elements of Harmony." All true. Zecora wasn't in Ponyville. Luna wasn't in Canterlot.

The Princess's lips parted slowly in shock. "Twilight! You were going to use the Elements of Harmony upon me?"

Twilight looked down. "I'm sorry, Princess. It was the only way I could think of to fight you. If I couldn't take you by surprise, I was going to call in my friends, and use the Elements to hold you long enough to use the charm. I was so scared, and desperate. It hurt to even think of it, but I thought I had no choice."

Celestia drew back a little, a spark of angry upset in her eyes, and was silent for a few moments.

Twilight waited, gazing steadily at the floor. Eventually, Celestia's expression eased, and her hand settled onto Twilight's shoulder.

"I know that you would never have conceived of such a thing, had the charm not entered your life. The fault is mine. Tell me of Pure Heart. What instructions have you left with him?"

"I had to charm him when he saw me, and would have called the other guards. I panicked. I told him to be loyal to me." Twilight embraced the coolness flowing through her mind, keeping her shame and horror far away. "I realised that I had changed him far too much. I was appalled. Once we had taken the Elements and resealed the vault, I undid everything that I had done to him."

"I shall have to make certain that he is free of further influence. How did you open the vault?" Celestia frowned slightly. "I had thought it secure."

"I have seen the vault opened before," Twilight said at once, with painstaking ambiguity.

"I will have to reinforce it. Tell me what you have done to the ponies you have enchanted, Twilight. How have you used the charm?"

Twilight looked away. She felt the quiet burn of her humiliation, her shame, and let truth spill from her lips to ease the difficulty of answering. "I cast it on Applejack, without knowing what it was. I've used it to make her attracted to mares. I did the same to Rarity. Applejack fantasised about being used, sexually, and I used that to make her agree to be enslaved. I made Rarity accept that I could enslave Applejack if I wanted, and something about that made her want to be my slave too. I seduced Rainbow, and charmed her to obey me. I seduced Fluttershy, and made her become my pet. I seduced Pinkie and charmed her to be part of my slave harem too. I charmed them to all accept my right to enthral anyone I desired. I made them line up to be fucked, and took them one by one with a sex toy. I made them use the toy on each other. I dressed them-"

"Stop, Twilight!" Celestia burst out, her eyes wide and her cheeks flushed. "I - I cannot hear anymore. Say no more."

"I'm sorry, Princess."

Celestia gazed fixedly away from Twilight for a long moment, and Twilight couldn't help noticing with academic interest that the Princess's chest was rising and falling quickly against the delicate white of her sun dress.

"I will accompany you to Ponyville and ensure no trace of your activity remains in your home." Finally, not looking around, Celestia added, "Is there anything else you should tell me?"

A hopelessly vague question. That gave her freedom. "I truly love Applejack, and she loves me. It happened because of the charm. You could just stop me using the charm, and leave that."

"No, Twilight. I cannot." Celestia straightened, and looked down at her. "You have said yourself that you enslaved her. That you have altered her desires to meet your own."

"I undid it. I removed all the instructions and asked her if she wanted to be with me, enchanted. She has always wanted a relationship like that, and we really care about each other. I care about all of them, but it's the most special with her. You could order me not to use the charm selfishly, and simply let us go."

"If only it were so simple." Twilight's heart sank as Celestia gazed into her eyes. "The charm is too dangerous. Even now, do you believe that if you were set free, you would never abuse the spell again?"

She couldn't think of a way to respond to that with a half truth. "No," she replied in a whisper.

"So you understand. I must remove all evidence that this spell ever existed. This time, I shall not make the same mistake. Then, once I am certain all traces are gone, I will have myself forget once more and it will be ended." Celestia's expression was of quiet, implacable pity. "I'm sorry, Twilight, but your relationship could never have come to be without the charm. I must make certain that you are restored to the way you should be, along with all your friends. Only then will I have undone the damage my carelessness has caused." Her voice lowered as she spoke, visibly pained to deny Twilight's request.

"Then please- make me forget now. I don't want to keep waiting for it to all be taken away." She needed Celestia to make her forget, before she realised the mistake she'd made. She'd managed to hide Zecora and Luna's enslavement. It might be enough. It had to be enough.

Celestia bowed her head slowly. "As you wish, my faithful student."

The world disappeared, replaced by darkness, and Celestia's gaze.

The Voice spoke to her.

Her memories vanished, quietly and without fanfare.

The cube fell from her hand. "I remember that day! I went to Canterlot, to see Celestia, and everypony came, and..." Her voice trailed away. "None of that was real. That was real."

The other Twilight leaned forward over the row of white cubes, their sunbursts glowing faintly. "Did you see it? Do you understand?"

Twilight nodded. "Yes. She's immune to the charm, but she said she was enthralled, to remove her memories."

"So the charm is modular. The section that attunes it to affect Luna can be removed."

"We can make one that is tuned for Celestia."

"Then we can fight her."

"And win."

"Yes."

Twilight surveyed the last few cubes, her eyes narrowed. "She used the charm again. On me."

"Temptation," said the other Twilight quietly. "You know she can't stop."

"Not unless I make her."

Twilight reached for the next cube. First, the rest of her memories. And then...

Then Celestia.

Author's Notes:

River Road called it; it was Trixie.

Revelations! Memories! Temptation! Seduction! Twilight vs. Twilight action! I'm having fun.

Proof reading by the splendid Setokaiva!