A/N:- This is a last minute addition. Originally, the chapter was different or to be precise the upcoming chapter was supposed to chapter 279.
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In a hidden dimension,
A bald monk with a long Mohawk is pinned against a giant tree. There are various vines attached to his body, as his body glows with a green hue.
Shoom…
Jigen slowly opens his eyes as a glint flicker through them. His right eye changes into a dharma wheel.
Fwoosh…
The scene of Izuna beheading Urashiki appears in his vision.
"Looks like Urashiki has fallen to this lowly human."
Hmm…
He notices the Rinne-Sharingan of Izuna as he ends Urashiki's life.
"He awakened the Rinne-Sharingan?!"
Surprise appears in Jigen's eyes as he focuses his attention on Izuna.
Swirl…
The wheel in Jigen's eyes rotates rapidly as tries to peer through Izuna's destiny.
Argh…
Jigen's expression turns ugly. A trail of blood leaks from his eye as he hurriedly closes it.
"I can't see his fate anymore. Looks like the strength of his Dojutsu is far superior to mine."
A grim expression appears on his face as he recalls the pattern of Izuna's Rinne-Sharingan.
"That pattern!"
He attempts to recall any information pertaining to Izuna's eyes.
"I can't seem to recall any information in the clan about the spiral pattern of his Rinne-Sharingan. It must be a mutation of some sort; otherwise, how could a bastard descendant of that Kaguya awaken those eyes?"
Resentment appears in Jigen's eyes as he recalls the betrayal of Kaguya.
Haha… Haha…
A series of laughter ring through his forehead as the consciousness of the real 'Jigen' appears in his mind.
"Karma bides its time, and it's your time for payback."
Hmph…
Jigen scoffs and uses his Dojutsu to suppress that consciousness.
"You are nothing more than a pathetic remnant soul lingering in this body. I would have destroyed your soul long ago if it's not for my unwillingness to stay in this body."
Jigen continues to recover using the chakra of the Chakra tree as he ponders over his next course of action.
"During the previous battle, the unexpected attack from that Izuna Uchiha caused far more damage than I expected. This body is already at its limit; if I try to push it any further, I am afraid it will perish."
Jigen stares at the failing organs in his body.
"I have sustained this body for thousands of years thanks to the chakra I secretly stole from the Chakra tree."
He stares at the small chakra tree behind him.
"This chakra tree results from the chakra I stole during the sealing of the Ten-tails. I groomed it into a new chakra tree once it turns into ten-tails; I will feed this failing body and accomplice my mission. Luckily, I managed to leave a Kama mark on that girl."
He closes his eyes and slowly merges with the tree.
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In a giant palace on the moon,
"Looks like an Otsutsuki member from the main family has perished on the earth."
A teen with pale skin and shaggy white hair turns in the direction of the earth. Six magatamas are tattooed around his collarbone to resemble a necklace.
"I wonder who could it be?!"
His eyelids are shut close as he continues to gaze in the earth's direction.
Rustle… rustle…
A wooden puppet walks towards him and bows.
"There is a plate of food in the puppet's hand."
The teenage kid turns towards the puppet and dismisses it.
"I am not in a mood to eat anything. You can leave now."
He waves his hand and continues to gaze at the earth.
Since his childhood, after his ceremonial sacrifice to Tenseigan, he has been locked up in this place.
'It has been ten years since father and mother left this world. I have always been myself."
Ten years ago, the centuries-long war of the Otsutsuki clan of Moon ended with the victory of the branch family. The Main family was annihilated by the branch family using the power of the Tenseigan energy vessel.
Toneri recounts his memories as the dying words of his father rings in his mind.
"Toneri! After my death, you will be the sole survivor of the Otsutsuki clan of the Moon. Our clan has lived on the Moon for centuries, as we protected the vessel of the Ten-tails.
However, over time, the sinister chakra of the Ten-tails altered our personality and made us fight among ourselves. Now, with the release of the vessel of Ten-tails and the downfall of our clan; you, as the sole survivor of the clan, should return to earth and start a new life.
You don't have to shoulder the burden of your ancestors."
"No, I don't want to." Tears run down Toneri's cheeks as he slowly wipes them.
"I have always been all alone by myself, locked in this palace. I lived in perpetual fear of assassination by the members of the Main family. Now, when everything is gone and I am the sole survivor of the clan; what is the purpose of my existence?
The culture of the Earth differs from that of our moon. How can you expect me to mingle with such people? Sniff…"
He wipes his tears and turns towards the palace.
"When I was a child, you took my light and sacrificed it to sustain the energy vessel of the ancestor. You did this for the greater good of the earth, to prevent the suffering of countless people on earth, to protect them from the terror of the Ten-tails!
And now look at them… they weaponise chakra and wages wars against each other. Sniff…"
A resolute expression appears on Toneri's face as he walks deeper into the palace.
"Since I have sacrificed my entire life for humanity; then I shall become the judge who will deliver the punishment to these sinners."
Toneri arrives in a giant underground room with a gigantic spherical energy vessel in the middle of the room. He stops and gazes at the energy vessel for a while before walking towards the shelves arranged around the energy vessel.
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Somewhere in the Land of Swamp,
In an underground laboratory,
Swish… swish…
A fair skin man with long black hair and tan eyes is operating on a person.
His hands move skillfully as he operates.
"It's done!"
Swish…
He flicks the scalpel and stores it in the interior pocket of his trench pocket.
ARGH… HUAAA…
The person on the operating table screams in pain as dark purple chakra rises from his body.
Fwoosh… Fwoosh…
The features of the person change rapidly as his body expands in size. Multiple totem marks appear on his body.
Saliva drools from his mouth as his teeth turn into large canines. His finger and toenails expand and morph into razor-sharp claws.
Fwoosh… Fwoosh…
A pair of flesh wings erupts from his back and the spine of the person extends and morphs into a long tail.
Grrr…
The test subject growls in fury. His eyes turn red as he riles up a massive amount of dark purple chakra.
Growl…
He roars with bloodthirst and lunges at the fair man.
"Another failure!"
Swish…
The man swiftly waves his scalpel.
Slash…
The head of the giant rolls down as the scalpel shines with a dark purple chakra.
"It's hard to find pure-blooded descendants of my Akuma clan. Only an Akuma clan member with a bloodline purity of fifty percent or higher can undergo the process of Demonification and retain his sanity."
Crackle… crackle…
Dark purple flames crackle through his palm as he throws them at the dead body.
The flames engulf the body and disintegrate it completely.
Fwoosh…
The flames morph into a demonic purple snake and enter his body.
"Let me pick up another batch of candidates."
He walks towards a wall and pulls a lever.
Swoosh…
Four containers filled with a transparent amniotic fluid pops out of the wall.
Hmm…
"A fresh batch!"
The fair-skinned man nods his head.
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A/N: - For people confused about the conversation between Jigen and Isshiki. Isshiki is the Otsutsuki who possessed the body of a human monk called Jigen. He didn't brand Jigen with the Kama, but instead directly possessed his body. So, Jigen is more like a puppet body of Isshiki, which he modifies however he sees fit.
In the case of a Kama seal, Isshiki separates a part of his soul and consciousness into a seal and brands another person. The Kama seal, when activated will slowly eat away the consciousness of its host and slowly modify his body. So, you can say the Kama is like a virus that downloads the backup of an Otsutsuki in a host.
I hope I am able to clarify it since most of the people weren't able to figure out how it works.