Several Years Ago
An adult man who appeared to be in his late thirties sat atop a great mountain while looking at the city below. A small boy with short orange hair then walked up and sat beside him. The small boy called out to him,
"Mom finished making the rice balls, let's eat!"
He laid the tray containing 2 rice balls on his lap. Without any delay or hesitation, the father quickly grabbed one and munched on it. The son scoffed at his pig-like dad, and in consequence, the father knocked him on the head.
"OW", he shouted.
"Maybe if you had some respect for your father I wouldn't have to hit you so hard Hikaru!", he shouted as he continued to munch on his rice.
Hikaru then asked, "Hey dad. You're a sorcerer, right? Why did you retire?"
The father thought about it for a good while before pointing at a large building that existed from a great distance.
"I used to go to that school with a group of friends you see. When we all graduated we decided to form a group and take part in a bunch of missions together" he said.
Confused hikaru asked, "What does that have to do with my Question?"
His father quickly knocked him on the head again before shouting, "LET ME FINISH MONOLOUGING YOU FOOL."
"So anyway we were fighting a super duper strong cursed spirit. And we were losing quite badly."
Interrupting him once again he asked, "Did you win?"
Succumbing to his sons' incompetence he said "We were losing quite badly. Luckily though I carried a special power that allowed me to defeat that curse, however, it came at the cost of my companion's lives."
Hikaru then asked, "What does that mean?"
He then replied, "This power is a burden that you will have to inherit someday. I was too weak to use it so I quit being a Jujutsu sorcerer. I guess what I'm saying is, do not ever let this burden become too heavy for you to carry. I was scared of losing my humanity to it, so when it's your turn to bear it do not ever use it."
Back to the present day
He quickly awakened to the sound of strings being drummed. The blue Oni had used its power to awaken Hikaru from the brink of defeat. His head was bleeding badly and his bones were broken, but that didn't stop him from getting back up.
He then thought to himself, "Why am I remembering that time now? Actually, I guess it is time I used it."
He began to laugh hysterically confusing everyone. Meiyang then asked,
"Have you gone insane?"
But Hikaru simply responded, "Sorry Old Man, but it looks like I'm gonna have to break my promise."
He then began to chant,
"Sea of Black, Lord Of Piety, Return from Darkness, Discard and Penance from rain and black Ashes."
Before allowing him to finish his incantation Meiyang commands the blue dragon to finish him off. The dragon charged another blue dragon's breath and fired it at the two hiding near the wall. Before the attack makes contact with Hikaru though he still finishes his incantation,
"With This Treasure, I Summon, Eight-Handled Sword Stationary pañca Wrathful Deity
The breath attack impacts the two causing further damage to the arena around them. As the dust clears and dies down, revealing to what appeared be a black Oni who took the blast.
It wore heavy black armor that protected its whole body, while its White long hair protruded from an opening in the back of its helmet. It too wore a black mask with a pair of two devilish horns sticking out from its forehead and as if to compliment its black aesthetic it carried a scabbardless black katana.
The audience was stunned at the sight, however the blue Oni was incredibly scared. It tried to run away but the Black demon quickly grabbed its head and crushed it instantly.
Hikaru then began to speak, "Once upon a time an ancestor of mine was once a part of the destroyed Zenin clan. However, he got into an argument with the clan's head at the time and got cast out. However, after collecting and mixing a variety of different cursed spirits he created this shikigami that's been passed down to his descendants ever since. It's forbidden to use as it targets everything indiscriminately even if you're an ally and I can't withdraw it for a whole 3 days. So don't bother crying when you lose, this is after all my trump card."
The Oni roared towards the sky as if it was writhing in pain. It then looked at the dragon before sprinting towards it at terrifying speeds. The dragon followed suit as it flew towards it while charging another breath attack.
The dragon released the attack before the two came into contact but the Oni tanked it without even taking a hint of damage. It jumped onto the back of the dragon sending it crashing towards the ground.
It then raised its sword into the sky before plunging it into the dragon's waist. It attempted to shake the Oni off by rising into the sky once more at tremendous speed, but the oni simply grabbed onto its tail even breaking some of its scales in the process.
The Oni then dragged the dragon back to the ground and took a great leap into the air despite its heavy-looking armor. As it raced back towards the ground the dragon released one final dragon's breath at the demon. However much like before it remained unaffected.
The Black Oni prepared a powerful slash that split apart its head from the rest of its body.
The Demon then noticing Meiyang slowly began walking towards her.
Meiyang shouted, "YOU KILLED MY LAST SPIRIT NOW WHY DON'T YOU DISPELL IT ALREADY?!?"
Hikaru responded, "I told you already. Once I summon it I can't withdraw it for a whole 3 days."
The demon began to speed up as it walked towards Meiyang. Her breathing increased as her legs began to shiver. She eventually fell from fear while shouting for help.
"SOMEONE HELP ME"
The Demon raised its blade and prepared to slash the now defenseless girl. She tried to crawl away but her arms had now given away. The Demon then dropped its blade at unimaginable speeds all just to kill the already defeated opponent.
Thankfully the leader of the China and Korean teams both blocked its strike with their weapons respectively. Akumu quickly jumps down and grabs the girl just before the demon overpowers the two.
Sung Gon-ill then shouted at Akumu, "Your team had something like this the whole time???"
Akumu quickly responded, "I didn't know about this either"
Enraged at its prey being swept away the Black Oni roared towards the sky as the eye holes in its mask glowed a dark red. It was now enraged.
It quickly soared over Haoran and prepared to split him down the middle, but this time he managed to block its blade by himself with his staff. He then whispered,
"Extend Ruyi Jingu Bang"
The staff then grew longer as Haoran whacked away the black Oni sending it a decent distance away. However, its heavy armor easily nullified any damage that was dealt.
Before the Demon could get up however Sung Gon-ill who had been standing by at the time shouted,
"Skill: Great Seal"
A multitude of chains then surrounded the beast pining it down to the ground. Frosty Whipp then spoke over the mic,
Well, this is an odd predicament. Shouldn't we evacuate everyone out of the arena?
The Crowd then shouted fearing for their lives as they quickly flocked to the exit gates of the arena.
The black Oni on the other easily breaks through the chains that bound it and change its target to the armoured-up Sung.
But then a lengthy black whip wraps around its leg and launches it into an empty side of the bleachers. Sung Gon-ill then shouted at him,
"WHY ARE YOU HERE? IF YOU HAD NOT APPEARED EVERYTHING WOULDN'T HAVE DEVIATED FROM ITS SET PATH SO MUCH.
Confused Akumu asks, what he was talking about. However, the roar of the Black Oni quickly interrupts them.
Even faster than before the demon jumps towards Akumu this time at a speed that not even he could keep track of.
But before the deity could pierce his neck, Gojo Owari teleports in between the two while smiling,
"What did I miss?"