Yes, you guessed it right! The Extermination Scale doesn't include Izuna's jutsus. However, the extermination scale is based on his combat prowess.
Every rise in level is an exponential increment in the destructive prowess of a jutsu, and every level is a barrier that is incredibly difficult to overcome.
If every jutsu in the range of 5 to 5.9 has the potential to wipe out an entire nation, then the jutsu from 6 to 6.9 possess enough destructive prowess to annihilate entire continents or multiple nations with a single jutsu when used with destruction in mind.
Izuna's Kekkei Shi falls into the category. There were only a few moments when Izuna used this jutsu. Even at those moments, Izuna redirected almost all the energy of the jutsu toward the sky and contained the blast radius within a certain range. These jutsus are double-edged swords.
This earth-shattering, sea-sundering, and heaven-rending jutsus are just the tip of the iceberg. Minato thought this might be Izuna's limit. Since too much power in the hands of a single person will corrupt their mind. However, the existence of higher beings, the otherworldly gods, who can traverse across dimensions and consider the lower being like them as livestock, widened Minato's horizon to a new world.
It was at this moment that he thought about a power much greater than the world itself. A power strong enough to destroy an entire world. Perhaps this was the power of those so-called GODS in legend.
So, at this moment, Minato added a new tier to the Extermination Scale, 'The power to destroy the world'. He thought that he wouldn't come to witness such power, however, he was proven wrong when the seal on Ama no Hoko was released. It unleashed a greater evil on the world that wanted nothing more than the destruction of their world. That evil possessed a power strong enough to wipe out the entire world in a blink of an eye.
"Perhaps to beings like them, our existence is similar to that of an insect, unworthy of their attention." Minato shakes his head and focuses his attention on the battlefield.
The report of a jutsu of 5.5 intensity boggled his mind since such powerful jutsus will usually appear at the end of the battle and will become the deciding factor.
'Looks like even after so much consideration and preparation, we might have undermined the gravity of this war. A situation which might be unplausible in normal circumstances had already made its appearance.'
He was the one who sent Sasuke to fight against the reanimated members of the Akatsuki. However, even in his wild dreams, he expected such a situation to occur.
'I hope Sasuke can escape on time.'
Minato isn't worried about Sasuke's safety since Sasuke has multiple life-saving trump cards and even possesses a teleportation seal to escape the danger.
"Sigh… we might suffer heavy casualty in that sector."
A jutsu with a 5.5 extermination rating has enough radius to cover entire villages. Given the speed of the allied shinobi force, it's impossible to escape unscathed from that sector despite the early evacuation order.
Back on the battlefield,
Sasuke has a grim expression on his face as he confronts Kakuzu's most powerful attack deployed at the cost of his life. He tightly clutches the teleportation fuinjutsu scroll in his hand and calmly calculates various possibilities and their outcomes.
'The most obvious and reasonable outcome for me is to use the teleportation scroll and escape from this jutsu. The current me is incapable of dealing with an attack of such caliber. So, this choice is the most logical.
However, the cost of this choice is the loss of every shinobi in this sector. Almost two to three thousand shinobis will instantly lose their life.' Sasuke weighs the situation.
'Sacrificing a few thousand to save one life might seem unreasonable, but it's based on the premise that I possess the power to stop this attack. It's not a matter of choice, but a matter of fact.'
Sasuke takes out another scroll from his pocket. He hesitates for a while as he recalls the importance of this scroll.
"This scroll is one of the gifts Izuna Nii-san gave me on my thirteenth birthday. He said that this is one of his most valuable possessions and I must only use it during a life-death situation."
Sasuke bites his thumb and drips a drop of blood on the scroll.
"Nii-san, I will put my trust in you. I don't want my comrades to unnecessarily sacrifice their life in this war."
FWOOSH…
Kakuzu's attack closes up on him and explodes in an earth-shattering explosion. A gigantic sphere of volatile energy encases the battlefield and rapidly expands outward.
Since Kakuzu used this jutsu at the cost of his life, he didn't have control over this jutsu. As a result, the flow of chakra followed the natural path of least resistance and expanded outwards.
The ground, the trees, the clouds — everything rapidly disintegrates into nothingness.
RUMBLE… RUMBLE…
Powerful tremors ran across the ground as the shockwaves from the explosion shift the tectonic plates underneath the earth and an earthquake erupt from the heart of the earth with the site of the explosion as the center.
The temperature of the surroundings rapidly rises by several thousand. Sasuke, who is the first to bear the brunt of the explosion, feels it the most.
Even before the blast from the explosion could reach him, the powerful shockwaves and the high temperature cracked and melted his full body Susanoo. The blinding light from the explosion strained his eyes and Sasuke to force to close them off to prevent damaging them.
It was at this moment when Sasuke thought he made a mistake by staying at the battlefield and was about to crush the teleportation seal to escape, the scroll in his hand shone with a brilliant blue light.
A pillar of cyan light erupts from the scroll with Sasuke at the center. The cyan pillar of light shrouds his failing Susanoo with a thin barrier. This thin film of barrier instantly blocks the heat and radiation from the blast.
Next, a colossal towering shield drops in front of his Susanoo.
Vrmm…
A powerful hum echo through the battlefield as the eyes of the Yaksha on the shield glow brightly with a green hue. Numerous inscriptions representing Fire, water, wind, Earth, and lightning becomes visible on the shield.
'This is Izuna Nii-san's ultimate defense.' Sasuke's eyes widen in shock.
He instinctively grabs the shield with his Susanoo. The powerful burst of nature energy from the shield stabilizes his Susanoo and rapidly repairs the damage. A four-layered barrier appears in front of his Susanoo and blocks the explosion from traveling further.
"This shield can store nature energy." Amazement flickers across Sasuke's eyes as he holds the shield.
The stored nature energy in the shield rapidly depletes as Sasuke understands the shield's usage.
'This shield slowly absorbs the nature energy from surroundings on its own and the wielder of this shield can use that stored nature energy as he pleases. When activated, this shield will deploy a powerful five-layered barrier. However, I am not strong to deploy all barriers and even these four layered barriers are the result of stored Nature energy over a long period. However, I have signed a contract with this shield and from now onwards I can use it freely.'
HAAH…
Sasuke infuses his remaining chakra in the Yata No Kagami shield.
"CONFINE!"
He yells in frenzy. The shape of the barrier around the shield shifts and it slowly confines the blast of the powerful explosion to a very small radius.
Sasuke's chakra drains rapidly. Beads of sweat perspire from his head as he opens his mouth and gulps multiple chakra recovery pills. A blue-layered barrier slowly surrounds the sphere of explosion and redirects it toward the sky.
"SUPPRESS!"
The confined explosion turns into a cylindrical pillar of energy and pierces the skies. After a few seconds, the burst of energy dissipates into the surroundings. However, the aftermath of the explosion is still visible to the eyes.
Black clouds appear in the sky. Bolts of lightning crackle across the clouds and strike down the ground. Ripples spread across Sasuke's Susanoo as a few bolts strike his Susanoo.
A heavy downpour rains down from the sky as this battle marks the end of today's day battle. The sun slowly sets on the horizon; however, Sasuke is still silently standing at the previous site of the battle.
His gaze lingers on the bottomless hole present in front of him.
Sigh…
Sasuke sighs and shakes his head.
He gently caresses the colossal towering shield and places it on the rear of his Susanoo.
'This shield is a huge boost to my combat strength.'
The Susanoo flaps its wings and takes off to the sky, disappearing from the visions of shinobis who were frantically watching the battle from a distance with reverence.
"He must be one of the tactical deployments from the headquarters." A few shinobis profusely discuss among themselves.
"Everyone, let's return to the camp!" The Captain issues the command as he takes a last glance at the vanishing figure of Sasuke's Susanoo.
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A/N:- My new Naruto fan-fic, 'The Rogue Demon of the Shinobi World' is out.
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