"Ah, of course." Yusei smiled, gripping the Ice Dragon Longsword horizontally. His entire body lowered into a stance facing Kayaba, assuming the form for the Kuzuryusen.
Kayaba's face was expressionless. He glanced at Shiro, who had broken free from the paralysis, and said, "I'm surprised. You actually broke through the game's settings with your own will. It seems your sister is not a simple person either."
Yusei didn't respond. Instead, he continued to gather his spirit, energy, and focus, preparing to unleash the sword technique he had created.
Kayaba stated, "It's useless, Yusei-kun. Your skills have been sealed by me. Only SAO's Sword Skills can be used."
Yusei remained silent. In the next moment, his figure suddenly vanished from his original spot, leaving only dust kicked up from where his feet had pushed off the ground.
Kayaba's pupils constricted sharply. He quickly activated the [Hawk Eye] skill, which could greatly enhance a player's eyesight and dynamic vision.
But the moment he activated Hawk Eye, he saw the longsword already in front of him.
'So fast!'
Kayaba saw the sword arriving before his eyes, but in the next instant, the cold-emitting longsword disappeared again.
A gust of wind passed by Kayaba, tousling his hair. He felt a chill, and Yusei had already appeared far behind him.
The sudden burst of speed from Yusei made Kayaba feel a bit apprehensive. But seeing that he had taken no damage, he couldn't help but laugh.
"Yusei-kun, what's the point of this?"
Yusei, with his back to Kayaba, said calmly, "Hiten Mitsurugi-ryu, Yusei-style: Extreme Sword Technique."
His voice was slow and steady as he announced the name of his new sword technique. But this only confused Kayaba, who felt the need to remind him again:
"Yusei-kun, I've already stated it. Those extra-ordinary sword techniques of yours have been sealed. They can no longer-"
As Kayaba spoke, he suddenly jolted to a stop. Instantly, numerous sword energy slashes erupted around his body, cutting into him.
He held his shield in front of him, but couldn't block a single one of the slashes. His HP dropped faster and faster, visibly about to bottom out.
Under the intense barrage of attacks, Kayaba was unable to defend. His HP actually hit zero directly.
He didn't shatter into data fragments like other players… because he was the Game Master. Even pulling out a revival crystal right now was a matter of a single thought for him.
But he didn't do that. Instead, he looked at Yusei with deep puzzlement on his face.
"Yusei-kun, just now... what was that?"
Yusei turned around, "That was a sword technique system I created based on the Hiten Mitsurugi-ryu's ultimate secret technique, Kuzuryusen."
Yusei glanced at Kaguya in the spectator stands. It was unclear if he was explaining to Kayaba or telling Kaguya the principle behind the sword technique. He then continued,
"Master Kuzuryusen thoroughly, achieve speed fast enough to compress the slashes of Kuzuryusen around the enemy, so that even after you leave the enemy's vicinity, the slashes can attack the enemy shortly after."
"The true difficulty of this move lies in whether you can compress the slashes into spatial dimensions. This requires you to have mastered Kuzuryusen to a proficient level." (A/N: It's referenced from DnF's Sword God. I found a skill that could be related to Kuzuryusen, so I made the connection.)
A look of understanding dawned on Kayaba's face, "I see. So it seems I didn't lose unjustly. In the end, this game couldn't bind you, could it, Yusei-kun?"
As he spoke, Kayaba already took out the [Seed of the World Tree] and let it slowly float down into Yusei's palm.
"This is the prize. Take it."
The moment the Seed of the World Tree landed in Yusei's palm, the system task completed automatically. It also unlocked a new mission, [Elements Required to Construct a World].
[Mission: Elements Required to Construct a World]
[Mission Objective: Wait for the World Tree's Seed to sprout and grow into the World Tree. (Can be accelerated by watering with World Origin Source.)]
[World Origin Source: The fundamental power possessed by a world. Can be obtained by interacting with the most basic settings of that world.]
[Mission Time Limit: None]
Yusei saw this task but didn't pay it much mind. His attention was entirely focused on the [None] at the end.
'No time limit? And no task reward either? Then no rush. Let it sit there for now. I'll deal with it whenever I have time.'
At this moment, the Roman Colosseum scene also disappeared. The black dragon, which had been getting blasted into disorientation by Kanna's lightning cannon, roared in pain once before also vanishing.
A line of text suddenly appeared on all players' game interfaces:
[Congratulations, you have cleared the game. You will be logged out within 30 seconds.]
All players were stunned. They were either grinding levels, eating, sleeping, or discussing plans for the next raid.
But none of them had expected... the game to be cleared so suddenly!
'Wha... what happened?'
Kiriko, who had been leveling in the labyrinth area, was also stunned when she saw the message. But she quickly reacted, a stunning smile appearing on her face.
Looking in the direction of the Knights of the Blood Oath's Headquarters, she murmured, "You really went and did it. And succeeded."
The SAO's game world began to collapse. Asuna, Shiro, Kanna, Kaguya, and the others had already disappeared.
When Yusei opened his eyes again, he found himself facing the slightly unfamiliar young man in a lab coat.
Seeing Yusei, he waved casually.
"Yusei-kun, congratulations on clearing the game. Do you have any thoughts about my game?"
"Thoughts... I should say thanks, I suppose. I originally entered SAO with the idea of bringing my little sister to play a game... As you guessed, I knew very early on that this was a death game."
Kayaba also let out a light laugh, "That makes sense. Yusei-kun, you possess miraculous power, just like this castle flying in the sky… miraculous and convenient."
Looking at the collapsing world, a reminiscent expression appeared on his face.
"My time is almost up. At the very end, to have witnessed that power which truly exists in the world... How wonderful."
"I suppose the dragon, Kanna, is such an existence... My childhood... my dream... ends here for now."
"Yusei-kun, you must definitely step onto that sky and soar freely."
"Finally, I wish you continued success and glory in your path."
Kayaba's figure had already vanished, leaving only his final words. Yusei listened silently.
He had already activated his own Sharingan.
Listening to the series of mission completion prompts from the system, he murmured, "I've actually always been soaring in the sky."