Prologue: Witch of Betrayal

All around her, there was quiet.

In the distance echoed the sounds of fighting, the thunderous booms of powerful Noble Phantasms clashing, the crack of smacking flesh, the rumble of the earth breaking and shattering beneath kicking feet and punching fists that surpassed the strength of mere humans.

And yet around her, there was nothing. She was alone with her own breathing, alone with the swirling of more magical energy than she had ever before witnessed with her own eyes. Nothing and no one stood between her and her goal.

Saber still fought far off. The remaining Masters were still busy with one another, trying to stop the Grail or bring it to fruition, each for their own reasons. In truth, the Grail War was still not yet finished, and the vessel prepared to accept the souls of the defeated had not yet been filled. A wish could not yet be made upon it.

And yet Medea stood before the Great Grail, and she was the victor.

"What was it you said to me?" she asked the silent air. The vast torrent of magical energy that roared around her like a hurricane seemed to drown her words out. "If I made it to the end against all odds and stood before the Grail to make my wish, you would kill me yourself?"

She should be laughing. She should be crowing her victory, because he had told her he would crush those who stood before the Grail with a wish in their heart, even if it was her, but he was nowhere to be seen. He could not enforce the promise he had made to her at the beginning of this all. He could not stop her.

Was that not something to celebrate? Was she not the winner of this Grail War? She had schemed and plotted and waited for this moment, biding her time so that she could sweep in at the last moment and claim the Grail for herself, and it had all paid off, now.

With this much magical energy, she could achieve anything she wanted. With this much power at her fingertips, why, she could build her own Grail and use it to fuel whatever sorcery she imagined. There was nothing beyond her, now. She could have her wish granted at a whim.

And yet… In spite of that…

Medea looked up at the womb of the Grail, at the grotesque visage of a skeletal, half-formed fetus with four enormous eyes and too-long limbs. The miasma of corrupted magical power that seethed off of it and hovered over the ground like mist was corrosive and vile, even to a Heroic Spirit like her who was formed more from grudges than adulation.

Even this was not truly an obstacle. It was exactly as had been foretold: a creature of incredible power that specialized in the killing of humans, a thing of darkness and curses closer to one of the Beasts, an Evil of Humanity, than a proper Servant. But it was still weak and defenseless, and therefore at her mercy. Like this, nascent and not yet fully manifested, she could smother it in its womb and plunder the Grail for whatever she desired.

This was it. This was what she'd struggled for, what she'd almost died for, this was the end of the crooked path she'd been walking. Right here, right now, it didn't matter if the Grail War hadn't technically ended, because with this much power at her fingertips, she was the winner, no matter what.

And yet…

And yet, she was hesitating. Victory was within her grasp, and all she had to do was reach out and take it with her two hands. There was nothing stopping her, nothing standing in her way, neither Servant nor Master to prevent her from subverting this whole system for her own ends.

And yet she hesitated.

Why?

Why? Why was she hesitating? What was stopping her from claiming her prize?

Nothing. She couldn't think of a single reason. There was nothing in her way and nothing at all to stop her. She had no reason.

No, that was wrong. It wasn't that she didn't have a reason.

Rather, the one reason she could think of was a reason she absolutely couldn't accept. She'd spent too much time and effort denying it, turning away from the possibility, and scorning him for his willingness to believe it. She'd spent too much time tricking him, too much time lying to him, too much time and effort twisting him around her finger.

It had all been a lie, it had to be. Yes, from the beginning, she'd always known she could do it, she would do it, and that she'd have to in order to make it this far. Lying to him and leading him on, tricking him into believing in her, trusting her, that had been part of the plan ever since he had saved her.

She'd even given him her body, made herself vulnerable just so that she could take advantage of his. Seduction was the witch's oldest trick, the original sin that men blamed her for. She had seduced Jason, surely, and killed her brother to sell it. What difference did it make if this time such an accusation was true?

And with her tongue, she'd promised him loyalty. With her lips, she'd sealed that promise. In the bedchamber, she'd given that promise weight. No man could surrender so much to a woman and not believe her his.

All so that she could do as her legend said she would and betray him at this very last moment.

But what if the only person she'd wound up lying to was herself?

Damn it. Damn it.

She drew Rule Breaker, held it out, gripped it with shaking hands. The easiest thing in the world would be to stab herself with it and be free of the contract, free to betray him and take the Grail, free of the threat of his Command Spells when he realized her treachery.

And yet, she couldn't do it.

No, she couldn't be that much of a fool, could she? That day, when he'd so calmly and with such conviction told her she could transcend her legend, she had scorned his naiveté. She had long come to terms with who and what she was and his pretty words wouldn't change any of it.

And yet they returned to her now.

"Self-actualization, you called it," she murmured. "To cast off the shackles of my legend and become a hero. A chance to be true to who I am, rather than who I was forced to be."

She'd derided them then, and she absolutely should, now.

But…

The phantom sensation of his lips on hers tingled. His breath on her ear, his fingertips dancing along her naked skin, his body flush against hers. The memory of his scars under her touch. The sense of calm contentment to feel the warmth of his body next to hers.

Why? Why couldn't she get them out of her head?

His trust, his belief in her innate goodness should be meaningless to her. How could it compare to the deepest, most heartfelt yearnings that had been carved so completely into her being that she felt them now, millennia after her death? It simply couldn't. It was the same as weighing a feather against a pile of gold.

But… In spite of that…

"You're a fool."

She spat the words out like venom. Even she wasn't quite sure who she was addressing them to, herself or him. Maybe she was saying it to both.

Who was the greater fool, then? The fool who believed in her, despite knowing exactly who and what she was, or the fool who fell in love with him, in spite of her intentions to stab him in the back?

Or maybe she was the only fool, for not knowing that she'd become so good a liar she could deceive herself so completely.

A month. That was how long it had taken him to win her over so thoroughly that she'd never realized it. A month. That was all the longer it took him to steal her heart.

It felt far too short. Maybe if her younger self had been summoned, she would have been so susceptible as to find him that charming. The Princess of Colchis may indeed have been so easily seduced.

But the Witch of Betrayal should never have fallen at all.

Damn it. Damn it all. And damn him, most of all, for making her love him.

Because there was no other choice she could make. Now that she'd come this far, now that she'd made it before the Grail, there was no other outcome that could possibly have resulted. This was a foregone conclusion.

Knowing what she was sacrificing now didn't make it hurt any less.

She lifted Rule Breaker, her Noble Phantasm that canceled all contracts and reduced all magecrafts back to their origin state. Her hands no longer shook, because she'd made her decision.

For a moment, she closed her eyes and didn't bother to hide the lone pair of tears that leaked out. She thought of her family and friends, the ones she'd left behind when she'd sailed off with Jason. She thought of her father, her brother who she'd mutilated, the various staff and ladies in waiting who had been kind to her. She thought, at last, of the young man who had been the first to offer her a real and true smile since that fateful day, the first since she'd left Colchis to honestly love her, whether or not she deserved it.

"I'm sorry."

And she thrust her crooked dagger down.