With Mangekyo, I Escaped Konoha To Other Worlds [Naruto/AttackOnTitan]

Ok, quick one. This Chapter is just to keep those who are still entertained reading and to post a message. This is also probably going to be the last chapter This week.

Why? Well The reason is simple actually. I read my own novel. Yeah, and frankly, I cannot believe I wrote it. I mean, something with so many inconsistencies was written and posted by me? 🤣🤣🤣🤣🤣 The Irony.

So, this is going to be the Last Chapter of This Version.

No, I'm not dropping the book. I made mistakes and I'm man enough to admit it. Thankfully, i realized it before taking the book above Thirty Chapters. If not I would just drop it directly and start all over. Plus I feel I can make it right.

So I'm going to do a soft rewrite. Starting From Chapter 8 upward. Everything before that will mostly stay the same unless I find a similar glaring flaw again.

If you still enjoy the Premise of This Story and Trust My Writing Quality, then come back around by This time Next Week.

I won't make heavy Modifications and several Anchor points I have used in following chapters after 8 will still be used just in completely different ways so nothing Too Drastic Changes.

So yeah, that's it. I posted this chapter instead of just leaving a message to get you guys acquainted with the Primary benefits of Seiji Copying the Levi's abilities.

If you feel there are any Inconsistencies, please let me know. Anything you have seen as a flaw in the story so far, please feel free to Point Out.

Anyway, Thanks.

Enjoy.

....

----

Trost, The Warehouse …

----

The tension was palpable, a suffocating dread creeping up as Kenny's fresh corpse began to leak blood.

Nevertheless, The Anti Personnel Squad all stood frozen, none of them daring to move a muscle as they warily watched the enemy in the distance.

"Captain Kenny … Just …."

"He's dead."

"… I can't believe it, how did he get in here? …"

Murmurs flooded from the Anti Personnel Squad. The shock at the death of their Captain clearly apparent.

"What are those idiots on lookout doing?…."

'Doing? They're most likely dead'.

Caven thought inwardly, her emotionless facade showing a clear crack. Wide eyes, open lips, pale expression, clenched teeth.

She understood what Seiji's appearance here meant.

'He must have followed me from The Garrison. That probably means Alton and Duran are dead as well'.

She had no time to process how exactly he was here despite turning himself in last time she saw him. The answer wouldn't solve their current predicament.

Just him being here meant bad news for all of them.

In the distance, Seiji's surprise lasted but a moment before returning to calm.

'Is he not an Ackerman? Judging from fight with Levi, I could have sworn he could dodge that'.

His thought process clearly showed that Seiji had never intended to kill Kenny. At least not yet anyway.

In fact, the attack was simply his way of announcing his presence. In Seiji's view, as the man who taught Levi everything he knew, Kenny should be capable of perceiving his attack and reacting accordingly. Either by dodging or blocking.

From the looks of it, Kenny did perceive his attack. However, he was unable to react in time.

'... Unable to react?' In that moment, Seiji paused, raising his hand to eye's length.

'I see. That's why ...'. Whatever doubts he had quickly faded. 'I can't believe I forgot to account for that. I made a mistake ... Again ....'.

Seiji exhaled, his mind going back to a few hours earlier, during his battle in The Northern Forest against Levi.

-----

Few Hours Earlier …

-----

Holding Levi against a Tree,

Seiji acted again. Levi was shocked to see blood leak from Seiji's right eye. But the latter didn't care.

"… Mangekyo Technique: Junen No Sozoku".

In an instant, a wave of pupil power erupted from Seiji's right eye.

'What the hell?…'

The struggling Levi was stunned at the sight of the bleeding eye of his opponent. Especially the odd feeling that followed.

Blood dripped from Seiji's right eye, sliding down his cheek. A sharp sting burned in his socket, but he barely acknowledged it.

Levi struggled against the tree, his narrowed eyes flickering between Seiji's bleeding Mangekyo and the overwhelming sensation creeping through his body. He didn't know what it was—only that something was wrong.

It happened then and there. For Seiji, a weird sensation pulsed through from his eyes as The Mangekyo Sharingan began to do its job.

It was not what he expected. The calming of Pupil Power expenditure turned into the exact opposite as Seiji felt the abundant fullness in his eyes being hollowed out. Disasters came in pairs.

Beginning with the consumption of Pupil Power, what followed was his chakra flowing in ways he didn't command it to.

Like a black hole, his Mangekyo swallowed his chakra in torrents without restraint.

'Shit?' Seiji nearly gasped in shock, feeling the drastic energy consumption. Initially, Seiji thought his first use of his Mangekyo was draining. Now he realized how mistaken he was.

This Pupil Technique didn't seem to care how much Chakra he had and swallowed more. Nevertheless, before he could begin to panic, a surge of The unknown flooded into his mind.

It was his Mangekyo.

In an instant, several lines of information and images emerged in his consciousness.

It carried Levi's body structure, the blood, bones, and cells. It was an analysis, the boy could tell.

Then that was further opened up as the information began to delve deeper on the molecular level. In that moment, Seiji saw it. Buried deep within, Levi's cells were filled with pulsing energy, burning with life and reinforcing Levi's cell structure to the maximum it could hold. It was a form of energy Seiji had never seen before. The feeling was foreign, alien, very, very different from Chakra and Pupil Power.

The images didn't go further, but the surge of information did. In an instant, Seiji understood. Not just what he was being shown but understood more on his Mangekyo Sharingan Technique.

The Right Eye, Junen No Sozoku. Initially, all Seiji knew was the vague descriptions once the Pupil Techniques were formed.

Now, more was revealed upon the first actual usage. The Mangekyo Technique wasn't a Copycat Replicator like he had initially surmised.

In truth, it was an analyzer, divided into Two parts. Its ability wasn't to replicate whatever ability he chose. Rather, it consumed pupil power and analyzed the Traits, usage process, and displayed effects of whatever ability he targeted.

This was the first part. The second consumed his pupil power and Chakra, to create a new ability or Technique with the exact displayed effects as the Target ability.

The consumption of Chakra and Pupil Power was directly proportional to the Target ability itself. In simple terms, the more outrageous it was, and the more it leaned towards laws that exceeded common practicality, the greater the consumption to replicate.

It was this core concept that enabled Seiji to use the copied abilities as his own despite not meeting the necessary requirements to actually obtain said abilities.

The implications were huge. Meaning as long as he has enough Chakra and Pupil Power, he could literally copy any ability of his choice, regardless of what they were.

Even replicating a Rinnegan technique was possible. Other Mangekyo Sharingan abilities, Kekkei Genkai's, he could have whichever he chose without worrying about any particular side effects associated with the said ability.

If Seiji had selected a Titan Form, he could directly bypass the need for Titan spinal fluid, Eldian biology and a connection to The Paths to achieve it.

This was exactly what was happening to him right now.

With his choice of The Ackerman Awakened power, Seiji's chakra was drained in what his Mangekyo considered Proportional to what he would receive in return.

'Is the Ackerman Power so exaggerated? What's with the Chakra Consumption?'

As if hearing his thoughts, The surge of Information continued. This time, not on his Mangekyo but on the Target ability itself. Junen No Sozoku was an analyzer.

Analyzing the target ability, sending the finished analysis back to its user. In an instant, Seiji understood what he was bargaining for.

The Energy reinforcing Levi's cells.

This wasn't a simple minor strength increase and Immunity to Mind Manipulation as he had thought. This was The Power Of The Titans.

Similar to chakra with Ninjas, it reinforced his physique, enabling him to achieve superhuman feats. The difference being Ninja reinforcement was an active ability while Levi's was Passive, Constant, always on.

The next process followed without his consent, with The Mangekyo carrying out the creation process.

Seiji felt it immediately. A shift. A ripple. I'm the process of his chakra being drained, a foreign force that wasn't his own surged through his limbs.

The transformation began after, starting with a faint vibration in his muscles, like an unsteady current struggling to find a path. Then, the sensation exploded outward, a violent expansion that rattled him to his very core.

His heartbeat surged.

His muscles burned.

Every fiber of his being twisted, contracted, then expanded—as if his body had just been reforged from the inside out.

Seiji didn't have Ackerman Blood. He wasn't an Eldian, and had no connection to The Paths. The source of Levi's strength was The Power Of The Titans fueling all awakened Ackerman's. It was a restriction, a requirement he did not possess.

Hence, The Mangekyo Sharingan was forcibly making the necessary alterations. Consuming his Chakra and Pupil Power to give him the equivalent effects of Levi's abilities.

How? Seiji didn't know.

But at the moment, he couldn't care less. Chakra in the Ninja world was created when the Physical Energy and Spiritual energy are molded together. Now, however, his Chakra was being used to give him much greater physical energy. Feeling the Chakra in his body be consumed massively in exchange for strength, Seiji almost grew intoxicated by the changes in his physique.

His breathing hitched. His fingers curled. His vision wavered, but only for a moment.

It happened then. A sharp, stinging pain spread throughout his eye sockets, waking him up from his immersion.

The very Nature of The Mangekyo Itself. An Eye meant to lose its light eventually. Compared to the first time two days ago, the feeling now was much more apparent.

Pain.

A surging pain, making him feel like his right eye was being burned. His vision blurred, the Chakra Network, especially the nerve pathways connected to his eyes, felt like they were on fire.

"Ugh."

In an instant, Seiji's felt dizzy, Levi right before him blurring into two. That alone was all the excuse he needed.

He had already gotten what he needed from Levi anyway.

Seiji disengaged.

His form flickered—vanishing from his position in front of Levi. He reappeared ten meters away, perched on the branch of a towering tree, his posture still composed but clearly strained.

His right hand pressed against his bleeding eye, fingers curled slightly as if trying to contain the searing pain. His breathing was heavier now—not ragged, but undeniably affected.

Damn… The cost of the Junen No Sozoku was far steeper than he had expected.

Even with the tenfold increase in Chakra reserves from unlocking his Mangekyo Sharingan, this single modification process had drained nearly half of what he had. Wasn't this thing supposed to be proportional to the Target ability?

Was Levi's negligible physical strength and unknown immunity To Mind Manipulation that valuable?

But it worked. He could feel the Chakra Consumption cease.

He could already feel it—his muscles were denser, his movements sharper, his reactions…

"Huh?…." Seiji paused, his expression clearly stunned.

'… Incredible …'.

In the distance,

Levi dangled from a tree, barely hanging on by a single ODM cable. His body felt off. The numbness in his left arm was spreading, his fingers twitching uselessly.

'…what is this?' He gritted his teeth, understanding the cause. Whatever that bastard had done, it had paralyzed his arm. Temporarily he hoped. Nevertheless, it meant one arm was out of commission. His fighting ability, whatever it was worth, had dropped by half.

'Tch … This isn't good'.

"I see." a voice brought him out of his thoughts. Looking at Seiji who had appeared far away. Clutching his bleeding eye.

Seiji clenched his fists, his knuckles cracking as raw, untamed strength coiled within them. His body felt light yet dense, powerful yet controlled. He could feel the change not just in his muscles but in his very perception of movement and force.

His balance adjusted instantly. His instincts screamed louder than ever before. It was as if he had lived this strength his entire life.

He turned his gaze back to Levi.

"So this is the power you were given?" Seiji muttered, his voice low, almost in disbelief.

It had been three days. His original chakra reserves had skyrocketed by more than ten times. He didn't even know how much Chakra he had anymore.

So why was the one use of his right eye so costly? Seiji only knew why after experiencing it himself.

Why were the Ackermans so much stronger than regular humans? From what he remembered from the anime, The ancient Eldian empire had sought to create more Titans shifters. The Ackermans were the accidental results of experimenting with Titan science.

Awakened members could manifest the Power Of The Titans as humans, without being a Titan or inheriting any of the Nine Titans.

In his last life, many saw this as an exaggeration. The Term "Power Of The Titans" didn't seem to fit what had been displayed in the Ackerman family. Be it Mikasa, Kenny or even Levi himself, all of them had shown greater strength, agility, durability, and endurance than the average humans.

However, compared to the sheer destructive feats of The Nine Titans shifters and regular Pure Titans above 4 meters, they simply paled in comparison.

Mikasa lifted several crates, Eren in the Attack Titan form, lifted a boulder. Levi threw a cart, Zeke threw horses across dozens of miles.

Seiji had just fought with Levi to properly gauge the Latter's strength. He had already estimated it.

Levi's physical strength was around Four Times stronger than a peak human.

Back on Earth, a trained boxer/MMA fighter could deliver a punch with a force between 225–450 kg (0.22–0.45 tons).

If the highest force was multiplied by four times, it meant Levi's full force punch could reach 1800 Kg (1.8 Tons)

This was enough to shatter walls, lift smaller cars and kill a fully grown bison with one blow. On earth, the statistics would be impossible. Here? Titans threw such weight around casually.

No matter how he looked at it, the numbers just didn't add up. Hence, Seiji didn't expect much when he copied Levi's physique. For him, the immunity to Mind Manipulation would be worth it.

As his two deadly enemies, Danzo and Itachi both had Mangekyo Sharingan with potent ocular Genjutsu. Each had a Kotomatsukami ready for use. Itachi even had a spare Tsukyuomi.

The latter was still doable. The former? Seiji wasn't going to take any chances. Even with this power up, he would try his best to avoid getting hit by Kotomatsukami at all costs.

The last thing he wanted was to get brainwashed into being a lackey of Danzo or Konoha. Levi had already proved immune to even Mangekyo Genjutsu.

If it was as potent as he assumed, then perhaps he could even deal with infinite Tsukyuomi. Point being, Seiji's expectations were on the Immunity To Mind Control, not Levi's physical prowess.

At base strength, a Genin was 2× stronger than a regular adult male without chakra. Weaker ones on par or slightly weaker than elite fighters, and stronger ones edging out.

A Chunin was 4× at the minimum without Chakra. Stronger Chunin had better physicality. Seiji himself was an Uchiha. Even if he was a Chunin, he was stronger than regular civilian ninjas and most ninja clans of the same rank. There were reasons why only the Senju clan could compete with the Uchiha at its peak. Only the Senju and Uzumaki could surpass the Uchiha in physical prowess.

Levi was 4× stronger than a peak human. Without Chakra, Seiji surpassed Levi in terms of physical strength. In movement speed and reaction time, the Ackerman was in the negative.Ninjas were naturally trained for Evasion and dodging.

He lost to Levi in terms of battle IQ and experience.

In all other aspects without chakra, although not crushing, Seiji was physically superior. Hence, he didn't have many expectations for a physical boost. Now however, he realized how wrong he was.

What flowed through the veins of The Ackermans was The Power Of The Titans. The reason they didn't display more than what they did was simply because their natural bodies restricted them from doing so. In the final essence, they were humans displaying power beyond what was physically possible. Like Captain America, super soldiers who had hit the limit of what their physique could bear.

Seiji's mistake came from the assumption that the Awakened Power of The Ackermans was a fixed increase.

After sparring with Levi, he assumed that the Awakened Power only allowed a grant him Levi's level of physical fitness. For the first time in his life, he had never been so happy to be so wrong.

The Fourfold increase was fixed simply because the human body couldn't bear any more than that. The Power Of The Titans was most effective on Titans.

With a human physique, It had reached its limit. It was different with him. Just like he said, Ninjas and humans were two different species. When Ymir Fritz relinquished The Power Of The Titans, all Titans ceased to exist. So did the Ackerman Power.

Meaning, Levi's true strength was only on the level of a peak human at best. As a result, the Power was limited to four-fold.

In his initial assumptions, Seiji had expected his strength to receive a slight increase, or no increase at all. After all, his base strength already surpassed Levi and linear stacking wasn't plausible.

What did he receive? Fourfold. You heard that right. On top of his base Physical Fitness, Seiji had received a fourfold increase.

Making him at the very minimum, four times stronger than Levi. Making him sixteen times stronger than the average human. That's almost 8 Tons of pure power.

And this was pure physical fitness. Without the addition of Chakra. With just this alone, Seiji's shortcomings in physical fitness had been made up for. Once he adapted to this, another major weakness would be made up for. Taijutsu.

A Jonin was two to three times stronger than a Chunin in base strength. With better control of Chakra, their strength was even more apparent. Now, Seiji had no reason to fear Itachi in Taijutsu.

Not to mention, these weren't the only benefits. It was that exaggerated.

In all this, barely ten seconds had passed.

The sound of grappling gears brought Seiji out of his thoughts yet again.

'Huh?'

Seiji returned, only to see Levi's figure disappearing into the distance.

----

He had no choice. He had to escape.

A sharp breath. A shift of his weight.

Levi twisted midair, his remaining hand launching a cable toward a nearby tree—his body moving with the practiced efficiency of a man who had survived the impossible.

With this ordeal, Levi knew that they had made a mistake coming out here. Whoever this Seiji Uchiha was, he shouldn't have been found.

'He's not human, that's for sure …'.

It happened then. Right away, a figure appeared on a tree branch up ahead.

The same clothes, the same red eyes.

Levi's face changed drastically, attempting to change direction. Unfortunately …

The moment Levi moved, Seiji exhaled, his fingers sliding away from his bleeding eye.

The flicker of motion below was all he needed.

His body acted on instinct.

BOOM!

A burst of Chakra. The tree branch beneath his feet splintered violently as Seiji vanished from sight.

Levi's escape lasted exactly two seconds.

A shadow appeared beside him in midair.

The last thing Levi saw was a flicker of red, the sharp gleam of a Sharingan—then darkness.

Seiji's strike was clean, controlled—the edge of his hand striking the base of Levi's neck with pinpoint precision.

Levi's body tensed for a fraction of a second… then went limp.

Seiji landed softly on the forest floor, adjusting his grip as he slung Levi's unconscious form over his shoulder.

His right eye still ached, but the pain was fading. The exhaustion, however, lingered.

'Alright, let's get this over with'.

---

Back to the Present – Trost, The Warehouse …

Kenny's body was still leaking blood, his lifeless form slumped on the cold wooden floor.

The Anti-Personnel Squad remained frozen, their eyes darting between Seiji and their fallen leader, their hands gripping their weapons—but none dared to attack.

Seiji, however, wasn't paying attention to them. His mind was still processing.

His attack on Kenny had been casual, a simple test of his new power. And yet… the man had failed to react entirely.

Seiji's gaze dropped to his hands once more. He flexed his fingers, feeling the raw, compressed strength beneath his skin. He had grown stronger. Much stronger.

And now, he understood why.

The Ackerman Awakening Power wasn't just a passive boost. It was a fundamental restructuring of the body's efficiency in combat.

Every movement felt smoother, sharper, more deliberate.

Every attack was instinctive, effortless.

Every reaction was instantaneous, as if his body had already calculated the outcome before he had even moved.

He had miscalculated before. He had expected Kenny to react—had expected a fight.

But now, it was obvious.

The gap was too large.

Seiji had not just become stronger. He had become something beyond human.

'I'm going further and further down the road to be overpowered. …. How …. Underwhelming'.

He sighed internally.

BANG!

It happened then. A gunshot.

'Oh, these guys finally react?'

Seiji thought, coming out of his thoughts as he disappeared in place.

The bullet missed his phantom.

'He …'. The male gunman who fired the shot hadn't reacted when.

SQUELCH!

A blade pierced right through his throat.

Seeing this, Caven yelled. "Take him down! Hard!"

The sound of rapid gunfire sounding in the warehouse.

Outside, a group of children playing ball were frightened by the banging sounds and hurriedly scampered away.

"Damn! Where is he?…."

"… I can't see him …" SQUELCH!

"Look out!"

"Behind you."

"No … No!…"

"Argh...."

Inside the warehouse, chaos erupted.

Men screamed and bodies fell. Blood splattered in all directions.

One by one, the squad fell.

Caven fired blindly into the shadows, her pulse thundering in her ears. Bullets tore through the air, but it was useless. Seiji was too fast.

Another soldier's death rattle. Then another.

Panic spread like wildfire. The elite executioners of the monarchy, reduced to hunted animals.

Members fell one by one, their numbers dwindling too fast for them to react.

Caven felt her scalp tingle. This wasn't an attack—it was a massacre.

"Scatter!" she barked, voice cutting through the chaos. "He's playin' with us! Get out of the Warehouse."

Her actions were fluent, her gear already in motion before she even finished her warning.

Seeing this, the frightened Squad members all did the same, abandoning the fight and running for their lives.

Firing her ODM cables toward the walls, Caven was pulled forward rapidly as she attempted to break through the windows.

However, in that moment, A Shuriken rushed out of the shadows, flying towards her direction.

Under her frightened eyes, it cut the Two hook lines on her ODM gear cleanly. Losing support, the female plunged downwards before she could make it to the window.

Smashing painfully into a crate.

"Vice Captain!" a soldier screamed.

"Forget her you idiot! …" He was quickly reprimanded by another.

"Save yourself."

Instantly, several figures burst through the windows and made it through the openings on the roof.

"…. Huh?"

"Oh my …"

The first thing that came into sight was a corpse on the roof with a Kunai lodged in the forehead.

Nevertheless, they didn't stop. Firing forward, their gear latching onto building structures in the distance before pulling them towards them.