"Fluffymountains."

Hearing her own name makes the two-tailed fox turn bright red for some mysterious reason, but the power of her anger is such that it doesn't break her war face or her concentration. For all that she might have bobbled the moment in a happier time, today she maintains her grip on her sword enough to continue dangerously gesticulating with it in a manner indistinguishable from attempted murder.

Avenger responds by turning away from her quarry and hefting her sword in the direction of all this flustered killing intent. The laser sword seems invincible matched against the flimsy curving blade pointing back at her, and is easily more than twice the size of Kat in and of itself. In any other scene this sight would be comical. Here it is merely strange.

It would be a very simple thing to ignore this little squeaking doll. For all that her fury made her dangerous she was nothing compared to the wounds Ivar had already endured, and with her Noble Phantasm still active even if Fluffymountains had been supported by her Saber self it would not make a difference. All she had to do is take the blow in exchange for the opportunity to kill Actia. But she does not make the move. Her posture is entirely that of someone who is taking this threat of a fight with full seriousness. 

"I have lost the ability to call myself Saber. You may address me as Avenger. Or Ivar," she smirks, "The Boneless."

She brings her weapon down in a perfect overhead strike. Her speed is beyond human comprehension. Her form is without flaw. But her sword hisses and sparks as it clashes with not one but two others and halts before the deathstroke can complete. Berserker snarls and hurls her away. Avenger offers a small nod in response.

"Nevertheless I do acknowledge I am the same being you made a pact with. You gave me my life when I asked for it. Though my former Master very thoroughly squandered the opportunity I meant to buy, I agree you have the right to kill me now if that is your will."

"Wh--" sputters Kat, "Why would? No, what, no! No!! NO! Who wants that? Who wants to go and kill anyone? That's exactly the icky nonsense I was talkin' abou-- oh there I go again with the accent thanks a LOT! It takes forever to start talkin' normal after I slip, y'know?!"

"...Very well then. You may correct my 'vibes' if you prefer, but either way do so with that sword in your hands. I will not honor our accord if you do not."

It is an intense battle that follows, though lacking in artistry. Katherine is far too nervous to follow through with any of her slashes and far too angry to invest in vigor, and so what unfolds is a somewhat jittery dance of maximum aggression. She is too close and too wild for Ivar to meaningfully block her, and too short for the majority of the enormous warrior's natural strikes. In short order Avenger's armor is marred with dozens of tiny cuts, while she is limited to only vertical slices.

There is no purpose for defense in Kat's case. Any one of these strikes would shatter her arms and legs all at once if she blocked them full on. But the predictable patterns are simplicity itself for a warrior of Berserker's caliber, who manages to hip check her Master out of the way or with a howl make her flinch in the exact perfect moment, or in one case lift young Katherine Isabella Fluffybiscuits up on a tiny rampart so that her sword manages to meet Avenger's blow before it can build any real power. And there are openings for her to make her own counteroffensives, but she accepts none of them. Her armor rattles from the concerted effort of holding herself back, but alone among Servants in the Sunshard War, Berserker has a legitimately positive relationship with her Master. And for the sake of that Master, she keeps herself as out of this duel as she can get away with.

Like this! Then like this! Finishing like this! Again! The Again is the important bit as it turns out, as the completion of these sloppy, petrified forms do very little to finish off an opponent as inevitable as Avenger. But it turns out that Yue got one thing wrong, for all the help she had. The duel is not always about the duel. [i]This[/i] duel is about dignity. About humanity. About saving the world. It is also about a single strike and all the heart and determination that a person can pour into it. 

It comes at last when Ivar changes tactics. She slips past Berserker by letting her giant sword fall out of her hands, and lunges with her flexible arm and powerful fingers instead. And with a palm the size of her head suddenly shooting straight at her, Kat reacts with the perfect poise to be expected from her long years of training:

She screams. She ducks and covers her head. She feels something pulling on her sword arm and reflexively jerks it out of that grip as though being trapped by anything was the scariest thing in the entire world. Somehow this translates into a flat thrust. She feels the sword sink deep into Avenger's chest, and immediately falls to her knees.

"I, I, aish! I, oh no, oh goshies, oh Miss Saber no I'm so sorry! Oh no oh no don't die don't die you're not supposed ta get swords there I'm pretty sure oh shoot shoot shoot heck hold on I'll pull it out! No wait is that worse? I'll leave it in! Oh no but that must hurt so much I didn't know it was gonna! Oh!!"

"Child."

"Y-y-yes?" sniffled Kat, now trying not to break into a full on sob now that adrenaline had well and truly got the best of her.

"It is," Ivar grunted. It was difficult to talk with a sword jutting out of her lung, "Your intention to save the world?"

"It, I, uh, um! I mean yeah! Yes! Uhuh! Y-you're not dead right? You're gonna help right? You got some kinda magic spell for this?"

"I do not, Fluffymountains."

"...Biscuits."

"What?"

"M'name's..." Kat buried her face in her chest and her eyes in the crook of her elbow, "Fluffybiscuits."

"...What?" said Ivar again, plucking the sword out of her body.

"K-KATHERINE ISABELLA FLUFFYBISCUITS!"

Ivar stood speechless. For a moment she seemed to be contemplating stabbing herself again. With legendary effort, she tossed it on the ground instead.

"Yes, well. I have felt your resolve and I accept it. By our terms I owed you one defeat. This debt is repaid. But I also owe you a victory. Will you expend that on my assistance with your quest to save the world?"

"D-d'you," sniffle-snorted Kat, "Really mean that?"

"It is Actia's scheme that the world needs saving from. I will not turn away from my revenge. But for the sake of an alliance I am willing to focus it on this."

"You... promise? You r-really, super promise to knock off all the creepy murder death stuff and just help?"

"I have never once allowed my oaths to go unfulfilled."

Kat's knees shook horribly. Her throat felt like it had gotten a stick caught in it somehow. She wanted to say something smart, but everything that had held her together was unraveling with a speed that made her yearn to scamper home and bury herself in Yue's sock drawer. Not that she still fit in there, mind, but it's where her brain went. And neverminding she had too much work in front of her to get away with that even if she did, no matter if she was about to get a helper who could actually speak in words or no. It had just... been a lot for her. This whole thing was a lot to ask of a house fox. 

She screwed up her courage one more time inside the creepy death castle, and nodded.

Avenger stood in silence, with blood still oozing out of the promise-wound. She turned her head around the room to look at Diaofei, and at Angelesia, and finally at Actia. All three of these girls lay sprawled and miserable in her power. Angelesia in particular looked about to die under the illness of the grudge she'd been forced to bear.

Ivar removed her mask. Underneath was the face of a young woman with hollow amber eyes. She plucked her sword up off the ground and walked away along the corridor to plant it in the slot she needed. The Fylgja rose at her command, and with legs at the end of its power reserves stepped foot by enormous foot over to the ruins of the shrine where the Giant had once rested. Ivar lifted her sword again, and the mecha took a knee in place.

She took a deep breath.

"By my Command Seal, I order... myself," she held the gleaming brand aloft in defiance of the woman who had decried their uselessness only after crushing her dreams with one, "Survive this."

It burned away and disappeared.

"Angelesia. My pilot. My queen. Your war is over. I release you from your duties; you may rest."

The throne she had been buckled into quickly unfolded around her and slipped into the strange mechanics of this place, dumping Angelesia on the floor. Almost immediately she began to wretch with horrible, violent lunges until with a horrible noise and an even worse smell she coughed up a seed, which withered to dust absent the mana source that was sustaining it. With a final quiet shudder, Lancer's Master fell asleep and lay still.

All at once a thousand wounds erupted violently across Avenger's body. She dropped almost to one knee, but clinging to her sword kept her feet. She stared through pain at Katherine Isabella Fluffybiscuits. And as she promised, she remained.