It's been a week since the fireworks festival, and Mei is staying at Amane cafe because she was living alone. After her father got caught, all the servants left. Due to Mei's beauty, she might be in danger if she's alone.
Bronya always visits the cafe to play the game consoles lying around the cafe.
Mei asked, "Was it alright to let Amou-san and Amane fight?" as she watched Amou dragging Amane outside the cafe.
"Don't worry about the small stuff. Despite how easy-going Amane is, he's still stronger than her," Chisato reassured Mei.
"I thought Amou was Amane's master," Luo Yan said as she watched her mentor destroy the door because Amane pulled the railing.
"As I said, I'm too lazy to fight," Amane shouted as he pulled the railings of the door. However, with Amou's strength, the railing broke, and she continued dragging Amane. "So let go of me."
"No," Amou refused to let him go and continued dragging him. "Luo Yan, open the Hyperbolic time chamber," Amou said, ignoring the others who didn't know about their ability. Amane sighed and flicked his finger, fixing all the things that got destroyed.
"I want to watch their battle," Kiana and Artoria voiced out their thoughts at the same time as they followed behind them and got inside, surprising Mei and Bronya.
"What is this door?" Theresa asked as she got inside out of curiosity.
"Bakatoria and Idiotka were stressing Da Bronya out," Bronya said as she stood up next to Mei, interested in the door, so the two of them followed inside.
Once they got inside the hyperbolic time chamber, they were amazed to see a large white blank space and watched as Amane and Amou started wearing their battle suits.
"Let's fight until one of us is unconscious," Amou said, giving him a crazy smile.
"Sure," Amane replied and murmured, "This day was supposed to be my holiday, but sigh."
"I already heard about this place from Amou, but wow, this place is large," Chisato said as she looked at the white blank space.
"How did you get something like this?" Theresa asked, looking around with interest.
"This place was supposed to be a secret," Amane muttered as he gave Luo Yan an apologetic glance.
Luo Yan nodded, accepting his apology, and she watched Amou with interest, curious about how strong she is if she goes all out as she said.
"Chisato used your Martial Spirit to protect the others," Amou said as Chisato used her Martial Spirit that was awakened by Gu Yuena.
A giant clock hand appeared from the sky, creating a massive transparent barrier covering them, except for Amou and Amane.
Amou's clothes transformed into a Miko outfit, and a thousand Japanese swords showed up, surrounding the two of them. "LET'S GO! Senbonzakura Kageyoshi!"
The thousands of swords transformed into Sakura petals, and with a single swing, Amane got covered by the Sakura petals. But Amane vanished.
Amou vanished from her place as she appeared next to Amane and slashed him. Amane smiled and said "Barrier."
A thick barrier was created, but it slowly crumbled due to the impact created by Amou's attack.
"How troublesome," Amane muttered as he blinked in front of Amou and punched her in the stomach. But Amou counter-attacked and kicked him from his chin, sending both of them flying.
A purple ripple appeared next to Amane as he held a sword hilt and suddenly blinked in front of Amou.
Amou's senbonzakura came back into a sword and deflected Amane's sword that was going for her neck. "HAHAHA! Give everything you have."
"This woman," Amane said as he smiled and released the sword, causing it to be thrown up into the sky.
Amane immediately kicked Amou, but she used her sword to counter-attack, causing Amane to be thrown into the sky next to the sword.
Amane kicked the hilt of the sword and sent it flying at Amou directly at the speed of light.
Amou, on the other hand, turned senbonzakura back into Sakura petals and deflected the sword.
Amou immediately let go of the sword as she crossed both of her arms, and Amane arrived in front of her, kicking her. When she got thrown away, Amane didn't let go of this chance as he blinked behind her and uppercut her, sending her to the sky. He blinked again and arrived at the top of her, kicking her downward, sending her flying towards the ground.
This continued until Amou grabbed Amane's feet and smashed him to the ground, continuously punching his stomach.
Amane grabbed her fist and kicked her in the face, sending her flying.
The two looked at each other, covered with blood, and their clothes were destroyed.
"HAHAHA! JUST LIKE WHAT I WANTED, FIGHTING YOU WAS REALLY THRILLING!" Amou shouted as she laughed maniacally.
"Let's go all out in this last attack," Amane said, giving her a similar smile.
"From hidden realms, chaos shall flow,
Unleash the storm, let dark powers show!" Amou chanted, intertwining her hands.
"Born of tempest, fists stand prepared,
Foes shall crumble, chaos declared!" A small red energy formed within Amou's fist, slowly changing its color.
"Chaos Fist!" Amou shouted, the once red energy transforming into dark energy, shaping her fist as she lunged at Amane.
"Dream tree, power true, Leaves of stardust, skies imbue! Set spirits free, dreams unwind,
New paths forged, illusions bind!" An illusionary tree began to form behind Amane.
"Imaginary Arboretum, bloom and rise,
Break the gloom, weave dreams in skies!
Magic's art, hearts ignite," The tree started to transform into a shape.
"A guiding light through the darkest night! IMAGINARY ARBOREAL!" Amane chanted as the illusion of a giant tree appeared behind his back and transformed into a giant wooden spear created by the Imaginary Arboretum.
"This is bad! These two went too far!" Gu Yuena shouted as she quickly cast multiple layers of barriers, reinforcing Chisato's barrier too.
A huge explosion occurred, destroying everything around. The once blank white space was now filled with black holes. Fortunately, Gu Yuena and Chisato's barriers protected everyone from being pulled into the black holes.
Amou and Amane continued to laugh like maniacs, thoroughly enjoying their intense battle.
Gu Yuena sighed, a mark forming on her forehead as she looked at the two responsible for the destruction of the Hyperbolic time chamber.
"So that's how the time difference happened inside the time chamber," Amane said. He carefully created a new type of barrier rune and imagined two boxes, Box 1 and Box 2.
In Amane's imagination, Box 2 was surrounded by multiple black holes on each side, while Box 1 was placed in the middle. Thanks to the black holes, time within Box 1 was accelerated.
Artoria, Theresa, Bronya, Luo Yan, and Mei were all shocked to witness the intense battle between Amane and Amou.
The clash of their powerful abilities caused the Hyperbolic time chamber to be destroyed. Everyone could feel the sheer force and energy released during their confrontation.
"Is this... the true power of their abilities?" Artoria wondered, her eyes wide with amazement.
"No, it's not a noble phantasm. They're just using chan't because of Amane, and Amou was just affected by Amane. Those are the abilities of their martial spirit, but maybe it's similar to a noble phantasm. Don't worry, Artoria, you have the potential to achieve their strength," Gu Yuena explained.
Theresa clenched her fists, trying to comprehend the scale of the battle. "Their strength is incredible. It's like witnessing the Second Eruption come to life," she said in awe. She added, "I didn't know that they are this strong. But what shocked me the most was Amane. How can a person like him, who loves peacefulness, be this strong?"
Mei didn't say anything. Instead, she let out a sigh of relief, seeing that both Amane and Amou weren't deeply injured. She wondered if they were really just training or if they were trying to kill each other.
Meanwhile, Bronya, who got into Fgo because of Amane, had stars in her eyes as she looked at Amou. She noticed that the ability Amou used was similar to Quetzalcoatl's noble phantasm.
As for Luo Yan, she clenched her fists with an excited glance at Amou.