(A/N)- Based on that awful scene in the Unlimited Blade Works route where Caster uses Rule Breaker—a cursed dagger that allows her to steal another Master's command seals and by proxy their Servant—on Saber, forcing her to fight her friends and allies.

Disclaimer: Nah-uh.

Rule Breaker

The ruins were dark. Too dark. It made him nervous.

"Damn… where the hell is Natsu?" Gray grumbled, peering off into the gloom of a dim hallway.

His Servant thrust an armored hand into his chest to halt his forward progress. "Master, be careful!" she warned.

Gray looked down at the gaping maw of blackness just shy of his feet, bringing himself to a quick stop. He inhaled slowly through his teeth at the close call.

"Thanks, Erza," he said, shooting a smile at his red-haired companion.

She returned the gesture, then shot a glance down each of the branching hallways to the side. "This way," she beckoned him, spotting the faint flashes of firelight from Berserker splashing on the far wall.

Gray ran after her as she darted down that hallway, her armor clinking in a steady rhythm. Left, right, then left again they turned, coming up upon what looked to be a wide chamber.

Dammit Natsu, when will you learn to follow orders? Gray complained to himself, wondering how Lucy was faring against the minor familiars without her Servant.

They pulled up short as a rush of heat blew past their faces. Unshielding his eyes, Gray saw the pitched battle between the fire-wielding Berserker and the dark-haired Caster. Minerva was using her space-manipulation powers to dodge each and every one of Natsu's fireballs, standing calmly in place as her image appeared and disappeared around the room.

"Ice Make: Lance!" Gray shouted, bringing his hands up to form the streaking ice projectiles.

Caught off-guard by the side attack, Minerva failed to move out of the way in time. Several freezing darts splayed into her side, throwing her across the chamber.

"Berserker!" Erza called, brandishing her sword as she charged into the room and took up position. "Fall back!" she ordered. "Seek out her Master; he cannot be far!"

"Aw, I can take her!" Natsu insisted. His flaming fists clenched stubbornly. Minerva was up now and Natsu leapt past Erza to rush her. "Fire Dragon's Brilliant Flame!" he shouted, his hands spewing forth fire in a massive burst.

Minvera merely used her powers to side step the attack, teleporting in close to unleash a magical blast of her own.

"Ice Make: Shield!" Stepping in front of the intended target, Gray put up a solid frozen barrier, that absorbed the brunt of the blast, sparing Natsu from being deep fried.

Erza used the opening to attack herself, swinging her mighty sword in a series of rapid strikes that Gray could barely follow.

It forced Minerva to back off towards the other side of the room.

"Three on one is hardly fair," she chided, wagging her finger in a 'tut-tut' gesture. Reaching into her belt she pulled out a gleaming, jagged-bladed knife. An evil blade it looked, dripping with malice. Minerva grinned eagerly. "Let's even the odds!" she crowed.

"Ha!" Natsu scoffed, turning up his nose at the small blade. He turned to Gray and Erza in disbelief, thumbing at the Caster. "She seriously thinks that dinky little knife is—"

"Natsu, put your guard back up you idiot!" Gray shouted, but too late, Minerva had manipulated the space in the room to place herself behind the ice-mage and his shield, between him and Berserker.

The jagged knife was raised high. Natsu's eyes were only beginning to widen in shock.

"Natsu!" rang out a shrill female voice from another entrance. Lucy stood in the doorway, hand raised high and screaming desperately, "To me!"

The miracle of the Command Seal took hold, moving Natsu faster than humanly possible, dragging him back in less than a blink to Lucy's side, out of Minerva's reach.

The dagger sliced air. Minerva whirled around, not wasting momentum, changing targets in an instant. The twisted gleaming blade now streaked for Gray's chest.

He knew he couldn't block in time, already dropping hold of his shield to try and at least raise his hands.

Gauntleted hands hit his shoulder, pushing him forcefully, with magically-enhanced strength. Gray gasped as he was rammed aside, hitting the floor hard on his left arm and raising his head just in time to see the cruel dagger burying its tip into Erza's breastplate, piercing through, as Erza took the strike meant for him.

The swordswoman was frozen in shock, looking down in horror at the blade buried in her sternum. There was no pain. No blood. What—

All of a sudden there was pain, a tremendous amount of it. Dark tendrils burst forth from her wound, lashing out around them, Minerva's sadistic smile gleaming white in the maelstrom. Erza shrieked, stiffening, her limbs twitching in place as electricity seemed to flood through her.

Gray reached out for her in panic. "Erz—aaah!" He suddenly doubled over as a burning sensation assaulted his hand, wrapping around the palm with his Command Seals. There was a tearing sensation. Something was ripped away from him; it almost felt like one of his limbs.

The burning stopped. Gray looked down at his hand, still intact, but missing the magic seals that marked him as a Master.

The seals that Minerva now proudly displayed on her own arm.

"Rise, my puppet!" she commanded with smug satisfaction.

Erza had been kneeling limp, her sword fallen by her side. Now, she reached for its hilt, slowly, awkwardly, as if fighting the movement. Her fingers closed on it and she staggered upright. Robotically. The motion not her own.

As his Servant, his friend, took up a place by Minerva's side, Gray realized what had happened. Somehow, Minerva had cheated. Broken the rules to make herself a Master. Stolen Erza from him.

And he saw red.

With a ferocious roar that would have made Natsu proud, Gray sprang up from the floor and charged Minerva.

"Give her back!" he screeched. "Give her back you witch! Erza ain't your slave!"

Minerva flicked him back with a sweep of her arm. Gray blew across the room, flung by the Caster's enhanced strength. Natsu and Lucy rushed to his side, grabbing up his arms to help him to his feet.

"Kill them all," Minerva ordered.

Erza's face strained. Her eyes met Gray's across the way, pleading, as she slowly raised her blade. "Gray…" she begged, her voice shaking with effort, as if her very voice was being constrained by the Command Seals on Minerva's hand. "Please… go…"

Gray shook his head, standing upright, Natsu and Lucy flanking him on either side and tensing for battle.

Like hell he was gonna leave her now.

"Not without you," he told her, icicles beginning to move up his arms.