Chapter 173: Divergence

"You... Who really are you?"

Inside the Emiya Residence's dojo, two identical girls faced each other. Due to their similarities, one would think that they're long-lost sisters. Their only difference is that one seemed dignified and the other seemed very cheerful.

Still, they are almost indistinguishable as even their voice and height are the same!

Castoria held a bamboo sword and swung it carelessly for a few times before responding:

"I am you... but not you."

Swooosh-!

"We lived in different worlds."

Swoooosh-!

"Has different fates."

Swoooosh-!

"Most of all, you are single while I am not."

Artoria's eyebrows twitched upon hearing that, but her expression swiftly went back to normal. Meanwhile, Castoria's stance became more refined with each swing, and by the tenth, she went into the same sword stance as Artoria.

"You haven't answered this question properly."

From their first encounter, Castoria withheld many information about her origins. She kept saying vague things such as the above, yet she doesn't bother clarifying them. Although, Artoria doesn't know that she'd only wanted to play around with her while spending time with her husband... alone.

That's right, everyone knows about each other. While Castoria accepted Nimi long ago, she doesn't know much about the other four. This caused her to be vigilant and less accepting of them.

Of course, they wouldn't fight just because of that. Castoria had done it a few hundred times with Nimi long ago, and only when she realized her childishness did she stop.

'I matured, after all...' She thought as she recalled her past memories. They are abundant, yet she holds each of them dearly. Hence, she immediately became serious when she knew about Shiro's predicament.

If they hadn't sealed their memories of it, successfully avoiding a contradiction of reality in relation to [The Root], she would've been a taciturn person instead of being playful in the final stages of their plan back then.

"You'll know more after this bout."

Wordlessly, Artoria took it as a signal to attack.

"Hup!"

Swooooosh-!

Swoooooosh-!

Bam-!

In that instant, Castoria felt the rebound behind Saber's attack. Though, she moved her hand on the grip swiftly, allowing her to withstand the rebound easily. This made the latter's attack negligible, allowing Castoria to separated from her in two steps.

She dashed once more and began her counterattacks.

Bam-!

Bam-!

Bam-!

At first, Saber is holding well against her quick yet slightly weak attacks. However, it changed when Caster suddenly made a move that took advantage over an almost non-existent flaw that appeared in her movements.

Bam-!

With that, Saber is pushed back by three steps for the first time.

'What?!'

Her vigilance heightened to its utmost while concentrating on her sword strikes. Soon, she began pushing back Caster once more. Albeit, it didn't last long as the latter broke through a gap in her stance once more.

'What?!'

Three step.

Five steps.

Ten steps.

All of a sudden, Castoria's attacks became completely unreadable. If Saber can see the future, she'll realize that Castoria's attacks are the counterattacks for the future blows of hers, making it unpredictable!

In short, Caster is more than five steps ahead of her, allowing her to dictate the flow of this battle!

BAM-!

The bamboo sword in Saber's hands flew to the side. Her eyes widened as she realized what the girl opposite of her had just done.

'It's like I'm facing Merlin..!'

From the smile that she had from the beginning until the sudden change of flow in this fight, it's as if she's facing her mentor—the man whose knowledge are unfathomably deep.

Though, she didn't know that the magus in front of her has an even terrifying depth of knowledge as someone who accessed the [Library of the End], Shiro's special domain that embodied his greatest aspect—wisdom.

Castoria slowly walked to the metallic box and placed back the bamboo sword in her hand. Strangely, it didn't show signs of breaking despite the intense battle just now.

Looking at the dumbfounded Saber, she let out a small chuckle and decided to explain everything.

"Let's start with this." She said as bright white light appeared in her hand before turning into a sword that Artoria is familiar with. "Did you know about its origins?"

"...I do. It is used to save the world once against an Alien God." Saber replied whilst hiding her confusion and shock.

"At least you know about it. Anyways... Everything went different in my world. Due to some lazy bums who never fulfilled their responsibility, this sword was never created."

Hearing this, Saber's eyes widened as she asked, "You mean... The world came to an end? Without [Excalibur], the future wouldn't have happened..."

In that cataclysmic event, Sefar was only defeated due to 2 crucial factors: The fusion of 12 Machine Gods as well as the creation of Excalibur. The former weakened the overpowered White Titan, and the final blow was dealt when Excalibur, supported by the entire world itself, managed to create a [Mana Burst] that overwhelmed Sefar's ability to absorb, hence she died.

"Un. Long story short, all kinds of lifeforms are wiped out except the faeries. It's not a pleasant world to live in, I say."

Castoria began explaining the general events of her lifetime—to be exact, her life in the British Lostbelt.

Many unique concepts are included there such as humans not being "actual" humans, [Rhongomyniad] becoming a form of magecraft, and the perils that almost brought the world to its end.

Thanks to Shiro's remote help, everything else went different. Her [Excalibur: Dragon Vein Burning Armament], Morgan's [Rhongomyniad: Spirit Vein Closing Armament], and Mash's [Black Barrel] completely obliterated Cernunnos, with its [Divine Core] disintegrated into nothingness.

However, there's still the [Underworld Insect] left in this case. Thankfully, Shiro managed to pierce through all barriers in reality and arrive there. While his strength is limited at that time, he faced off against the terrifying creature that resulted from thousands of years of planning.

"Kya..! I can still remember how cool he is that time! Something like 'I'll take care of this.' and his beautiful eyes..."

For the time being, it turned into a romantic story...

*****

As the scent of the breakfast reached the other guest room, Rin is instantly jolted awake.

"Enemy?!" She shouted in panic.

Seeing that there are no one inside the room except her, she soon calmed down. Though, Rin noticed the smell of the breakfast from the kitchen.

In an instant, she fell into a daze. Unknowingly, she opened the door and briskly walked to it, only to see two guys, cooperating in an extremely precise manner, as if they had known each other for years.

Then, she saw the two identical "Saber" agreeing on something as they nodded together.

"Two... Sabers..?"

In that moment, Rin's brain short-circuited...

*****

A/N: Rin should go "BAEEEBERRRRRSSS???!!!" at this point...