Haruyuki and Kuroyukihime only had 50% of their HP left, and so did Kirito and Asuna. It was a deadlock on both sides, but one side had a healer that could bring them to full strength.
"Umm… if you guys want, I can heal you-"
"That won't be necessary, Chiyuri-kun.", Kuroyukihime interrupted.
"Because right now…", Haruyuki added.
"That would be dishonorable to our opponents."
"We're now more determined than before."
They both said these things at the exact same time, making Chiyuri know that they were in sync with each other as they stood.
Just then, Megumi stepped in, wanting to help her dear friend.
"Alright then, I suppose I should prepare a more suitable stage for you two lovebirds."
Her quick-witted remark earned visible stares from Haruyuki and Kuroyukihime, but Megumi paid it no mind and readied her wand.
"Paradigm Revolution!"
An aurora enveloped around them, signifying the transition to a new stage.
However, Asuna immediately recognized this ability and readied a countermeasure. She pointed her rapier towards the expanding aurora.
'Laaaaaaaaaa…'
A heavenly choir was heard, and with it, the aurora quickly crumbled and disintegrated.
"No way… my Paradigm Revolution… was cancelled!"
"Valiant effort, young girl. But that ability… is a derivative of what I used long ago.", Asuna responded vaguely to the attacker in her royal tone.
As she said this however, she fell into a strain. Haruyuki quickly realized something at that moment.
"I see! That ability must be quite taxing on Asuna-san. In which case…"
"Now's the time to strike!"
"Wait, Haruyuki-kun!"
Haruyuki charged at an insanely fast speed to the now vulnerable Asuna with his Lucid Blade, but he was stopped short by a parry.
It was no ordinary parry as her rapier emitted a purplish light, and Asuna had swung it without a hint of consciousness. Just then, she grew angelic wings and appeared to call out to someone, which Haruyuki could barely hear.
"Thank you, Yuuki."
As she mentioned this unfamiliar name, she proceeded with a thrust. Then a second thrust. Then a third. This went on until she had Haruyuki locked in a chain of nine consecutive attacks, as part of a ten-hit combo. He thought he could break free after the tenth hit.
However, Asuna was not done. She poured out everything she had into one last attack.
"This is… the final hit!"
"Mother's Rosario!"
""Vorpal Strike!""
Kuroyukihime and Kirito were battling ferociously, calling out a move that both of them knew. The impact from the same Sword Skill on both sides was enough to disturb the air.
Clashing their swords against each other, they had been locked in a state of near endless combat that would have been tiring to normal players. It was clear they had unbelievable amounts of stamina and strength, seemingly originating from the darkness they bore in their hearts.
"Death By Barraging!"
Kuroyukihime called out this special technique, which was only a step below her real killer move. She wanted to gauge her adversary's true potential.
"Starburst Stream!"
Kirito countered it quite easily, using the sixteen-hit Sword Skill she was well familiar with.
"I knew it."
"Hmm?"
"Two swords, dressed in black… using the same moves that he used… you are connected to Graph in some way."
"Well, actually… it's more like you are connected to us. But I'll explain everything later."
That made Kuroyukihime even more determined to defeat them and find out their secrets.
"Alright then, here goes, Black Swordsman – Kirito!"
"Bring it, Black King – Black Lotus!"
Just as she clashed swords again, she caught a glimpse of her partner's battle.
Haruyuki stopped short upon receiving the full brunt of the eleventh hit of the Sword Skill known as Mother's Rosario. He nearly blocked it with his Lucid Blade charged with his Incarnate technique, Laser Sword.
"Hmm, you're pretty good."
Haruyuki heard a voice, not that of Asuna's, but the spirit who guided her, seemingly the original owner of this Sword Skill, whom she called Yuuki.
"Yuuki… wait… where have I heard that name before?"
One of the documents his father had left behind talked about the 3rd generation FullDive device called the Medicuboid, used to make a breakthrough in medical treatment. It was first tested at the Yokohama North General Hospital, with the first recorded patient to use it being…
"Konno… Yuuki… so that was you who was passed down as a legend? You're… Zekken-san?"
He had also heard about a player from long ago named Zekken, which meant 'Absolute Sword', who was known for using the same eleven-hit Sword Skill that Haruyuki laid eyes upon.
But it was too late to speculate further. Haruyuki was nearing his mental limits trying to deflect the Sword Skill as much as he could and was about to collapse.
"Well then, how about we finish this-", Kirito requested, ready to deliver his final blow.
But Kuroyukihime cut him off.
"Starburst Stream!"
She launched sixteen bursts of energy from her blades onto Kirito.
"Hmm, so it is the same name, but a different technique…", Kirito thought.
"Haruyuki-kun!"
Kuroyukihime rushed to catch Haruyuki who was falling after his duel with Asuna, temporarily transforming her blade arms to hands using Incarnate.
"Senpai…"
"What do you say we beat them together?"
"But how?"
"It's simple. We combine our avatars like we did last time."
"Last… time…"
A few months ago, Haruyuki and Kuroyukihime, along with Chiyuri and Takumu, were sent into Accel Assault 2038 to stop the last remaining Assault Linker, Dushka 30, from wreaking havoc on local school networks. They managed to combine their avatar's powers in order to defeat her.
Such a trick was possible only with Incarnation, which was used to synchronize the quantum circuits of two Burst Linkers. Even as 'parent' and 'child', said to be the strongest bond in the accelerated world, they had to get the synchronization absolutely perfect, so they decided to use this trick only as a last resort.
"But…"
"If there's any time to use it, it's now. We're both bound by Sudden Death, remember?"
"Yes…", Haruyuki nodded.
"Besides, you just said these wings were mine as well, right? In that case, I can't let you take all the glory."
"…Understood. Let's do it!", Haruyuki responded, defeated by her unique way of reasoning.
They synced together and fused their avatars using Incarnation, just like last time. This time, however, it was much easier having experienced a direct connection between their Neurolinkers. And so, the obsidian avatar of Black Lotus ended up growing matte-black wings.
However…
"We're not done yet!"
"Activate! Metatron Wings!"
Kuroyukihime also decided to use Haruyuki's connection to Metatron to gain an extra pair of wings for some real speed.
Just then, an angry Metatron started speaking in their heads:
"Servant, I do not approve of you lending my wings to her!"
"Metatron…"
"But I shall overlook it this time. After all, our opponents are quite the formidable bunch."
"G-Glad you understand…"
With a final reassurance from Metatron, wings started to grow on the lower half of her avatar. They began overflowing with Incarnate energy arising from Haruyuki and Kuroyukihime's shared desire to fly towards the horizon. All this gave rise to the appearance of a splendid butterfly. As the avatar took form, she called out to the two in her head:
"Haruyuki-kun, Metatron, thank you for letting me fly alongside you. Now, I can finally be the butterfly I've always wanted to be."
"A-Amazing…", Niko let out a gasp.
"I see it now, Papa, Mama… the miracle that you always spoke about, is being created by those two.", Graph silently spoke to the swordmasters above as he witnessed the birth of the new avatar before him.
The rest of Nega Nebulas also looked up in awe at the shining brilliance of the first combined avatar in the history of Brain Burst. Acknowledging this as the ultimate power a Burst Linker can have, they decided to entrust their hopes to the new avatar before them in the form of Incarnate energy flying like stars.
As a result of the overflowing positive energy, Kuroyukihime experienced a warmth inside her she had not felt in a long time. Her heart was finally able to respond to her legion.
"I see. You're all… reaching out to me earnestly. Then… I shall accept your hopes this time."
As she accepted this light with help from Haruyuki, the obsidian avatar changed its color to the purest of white, along with the wings that were attached to it. Kirito and Asuna smiled, seeing their opponents' true potential being awakened right before their eyes, resulting from the strong bonds that Nega Nebulas possessed.
Kuroyukihime simply looked at her two opponents and shouted:
"Now then, let's go! Light Speed!"
She flew with an immense speed towards both Asuna and slashed her with a move that took out most of her remaining HP.
"Asuna!", Kirito called out to her, but he too was taken out in a blitz.
They were close to the ground, almost empty on HP, but they still had one final option. Kirito flew close to Asuna and said:
"We have no choice. Let's use that combo!"
"Alright!", Asuna responded, as she understood without words what she needed to do.
They readied their swords in hand and looked towards the butterfly avatar, preparing to perform their final move.
""Triple Sword Dance!"", they both shouted in unison.
Just then, the butterfly avatar also called out an attack name:
"The Eclipse!"
Kirito and Asuna once created a Sword Skill from their years of working together as partners. The attack known as Triple Sword Dance was a combo that brought out the full power of the two swordsmen, by firing alternating slashes at their opponents, giving them no time to react against one or the other.
In the past, they tried to recreate this attack by timing the hits of their strongest individual Sword Skills, Mother's Rosario and Starburst Stream, but there were very special circumstances that had to be achieved for them to be able to use both techniques, so they were unsuccessful in bringing out the true power of Triple Sword Dance for a while.
Meanwhile, Kuroyukihime's attack, The Eclipse, was a combo of twenty-seven hits executed in less than three seconds. Though it was derived from Kirito's final Sword Skill with the same name, she ultimately made this attack her own and brought out an even greater power than what it originally had. With the power of her strikes, and the speed she had obtained from both Haruyuki and Metatron, she was sure to win.
It was a vicious battle in the air, producing shockwaves with clash after clash. The two combos were evenly matched, until Kuroyukihime exhausted all of her twenty-seven hits and got pushed back. Kirito and Asuna tried to execute the last three hits.
"This is the end!"
"Not yet! Ektenia!"
Haruyuki called out the name of Metatron's second special attack, which shot feathers from her wings at a high speed to push them back. Just then, Kuroyukihime launched a Vorpal Strike from her left hand aimed at Kirito, and a Laser Lance on her right, fueled by Haruyuki's Incarnate, aimed at Asuna. The two moves went straight through their bodies, which ended up depleting the rest of their HP.
"We won… we won, Senpai…"
Haruyuki could not help but be shocked at the fact that he actually defeated the most powerful opponents he had ever faced.
"…Yeah.", Kuroyukihime affirmed with a smile.