Arriving in the Naruto world by filling out a form

Once he decided to use the remaining time on the intelligence boost, Ren opened up his mastery panel again. He had 3 minutes left on the timer, and if he wanted to make full use of them, he couldn't afford to waste the boost on something too obscure or overly complex. At the same time, using it on something too basic would be just as pointless.

His eyes scanned the panel, looking for the next best options. Eventually, they landed on two things: elemental releases and yang chakra. His yang chakra was already sitting at 84%, the highest among all his releases. If he didn't use the boost on that, then he'd be an idiot, and probably get mentally cursed by that higher intelligence version of himself again.

As he kept running through different ideas and potential benefits, his gaze drifted to the 81% mastery of Earth Release.

'Steel Release,' he thought.

But then he shook his head. 'No, Steel Release, even if not explained in detail probably uses Yin Release, not Yang.'

Yin Release governed form, shape, and conceptual transformation. That meant it could refine or reshape earth into something like steel, not just physically, but through a kind of spiritual or mental manipulation. In other words, turning earth into steel would require altering its fundamental nature, and that was Yin's domain.

'But what if I don't change its basic form?'

His eyes brightened slightly as the idea took shape. 'What if instead of using Yin to refine it, I just use Yang chakra to strengthen it? Not to transform it, just enhance its inherent property, which is durability.'

That made sense. If Earth chakra represented solidity and endurance, then Yang could be used to enhance those traits internally, within his own body and if he combined those two properly, then perhaps he could harden his body using Earth and Yang chakra in a similar way to how Kirishima's quirk worked in the MHA world.

'Since I already rely on taijutsu in combat,' he reasoned, 'a body hardening technique like that would be insanely useful.'

But there was a catch. 'The only problem is, would less than 3 minutes be enough?'

It wasn't a complex kekkei genkai like Lava Release or Scorch Release. It didn't require working with multiple natures or external elements. This was something he'd be doing purely to his own body, using two releases he already had good mastery over. That made it more manageable. But even then, combining elements with precision inside the body wasn't easy. It required extreme control over both Earth and Yang chakra.

He exhaled slowly, thinking it through again. 'Compared to FTG, this body hardening idea is much simpler. I already spent 7 minutes just understanding the basics of Flying Thunder God, so improving it further would probably take more than the 2 minutes I have left. Hardening, on the other hand, might actually be achievable in that time or at least partially.'

Even if he failed, he knew the attempt alone would give a good boost to both Earth Release and Yang Release mastery. It wasn't a total loss either way. But he still couldn't decide. Part of him argued that any progress on FTG, even minor, could be useful right now. But another part of him knew that he wouldn't be using FTG in public anytime soon, while hardening would have real and immediate combat benefits.

Plus, no one would be surprised if a taijutsu-based genius like him suddenly developed a new defensive technique. In fact, most would expect it. He was already known for being durable in close combat. It wouldn't be out of character at all.

Still unable to come to a decision, he pulled out the "sacred stick" from his belt and placed it at the intersection of four tiles on the floor.

'If it falls to the right side, I'll use the 3 minutes for FTG,' he thought. 'If it falls to the left, I'll go with hardening.'

He whispered the sacred prayer, let go of the stick, and watched as it landed in a straight line.

Neither left nor right.

He stared at it in silence.

"...You little bitch."

In a fit of annoyance, he snapped the stick in half and tossed it aside. Still frustrated, he stormed out of the basement, eyes darting around until he spotted Kimura lounging nearby. Without wasting a second, he closed the distance and shouted:

"Kimura! One of your hands is 'yes,' and the other is 'no'!"

Kimura blinked in confusion, sitting up as Ren rushed him.

Ren didn't wait for a response. 'Should I use the 3 minutes for hardening, yes or no?' he thought, reaching out and grabbing Kimura's left hand.

That was the subconscious trick, right? Left hand means 'no,' doesn't it?

But then Kimura spoke, still puzzled. "This was the 'yes' hand."

Ren froze, stared at him, and slowly backed away. Then, without another word, he turned and marched back toward the basement. Just before disappearing through the door, he shot Kimura a final glare.

"Why are you sitting around doing nothing? Go train or something. Strength doesn't come for free."

He gave a dramatic "hmph" and slammed the basement door shut behind him.

Kimura sat there blinking, still trying to process what had just happened. A while ago, Ren had told him to stay hidden and lay low so he wouldn't get exposed. Now he was yelling at him for not training.

"...Didn't he ask me to stay in the house so I don't get spotted?" Kimura mumbled.

But then he shrugged. 

"Eh. If he wants me to train, I'll train."

And with that, he went off to do just that.

~~~

Now that Ren had returned to the basement and the signs had pointed for him to choose hardening over FTG, he would do just that. His mind moved to the thought that had struck him earlier: hardening. It wasn't the Earth Armor Jutsu or the Earth Spear Jutsu which Kakuzu used, no, it was actual reinforcement of the flesh and bone using chakra from inside the body. Something that could be maintained in motion, under stress, and ideally in sync with taijutsu.

He didn't activate the boost yet. First, he went over his reasoning again to confirm it. Steel Release, probably required Yin to redefine the nature of the material to alter the concept of earth into a harder substance, like converting it mentally and spiritually into steel. But he didn't need that. He didn't want transformation. What he wanted was amplification and reinforcement.

If Earth chakra represented solidity and structure, and Yang represented vitality and the physical body, then their combination inside his own flesh should, in theory, make his body denser and more resistant.

If it worked.

He tapped his finger on the ground a few times, checking his chakra levels. He'd recovered all of his chakra, and this wasn't going to be a flashy jutsu, it was going to be small-scale, internal, and heavily reliant on chakra control. His Hyperfocus also improved both his control and his perception of chakra, and what he wanted to achieve was exactly the kind of thing the Intelligence boost would help with most.

He gave another command, 'System, begin the boost.'

Immediately, the timer appeared again: [02:51] and began ticking down.

Once again, the effects were immediate, like a set of weights being lifted from his mind. He breathed in.

'Hardening.'

He closed his eyes and visualized his own muscle structure, mapping out the chakra flow that ran through it. His knowledge of anatomy was strong due to how advanced his medical-nin training was, but with 93% chakra control and 99 Intelligence, he could now map and simulate the major pathways like water mapping the grooves in earth.

The first step was obvious, infuse chakra into the muscle tissue, but not just any chakra.

Yang chakra.

His first goal was simple. Find a way to thread Yang chakra through his muscular system and see what happens. He started with a small portion, sending it through his arms, wrapping it around the muscle fibers gently. As it circulated, he noticed his arm temperature rising slightly, and there was a faint tension building under the skin. There was nothing dangerous yet, but it meant the chakra was stimulating activity.

Just like how Tsunade's Chakra Enhanced Strength relied on precise control over physical energy, he was now applying a similar technique, but without external burst. He was just reinforcing instead of amplifying outward, but instead of normal chakra he was using Yang Chakra.

The Yang chakra moved smoothly, which was good, and his control was enough to keep it from overheating or tearing anything.

'Alright,' he thought, flexing his fingers slightly and observing the way his muscles responded. 'They're a bit tighter and denser, though the difference is not huge at least there is still a change.'

Now came the more complex part. He opened his eyes and looked at his hand. It looked normal, but felt heavier.

It was time to test what happened when he introduced Earth chakra into the system.

He exhaled and brought his focus to his right forearm. Slowly, carefully, he began to layer Earth-nature chakra into the muscle, right along the same path the Yang chakra had taken.

Almost immediately, he felt resistance. Not rejection, but structural feedback.

Earth chakra was naturally sluggish, and it resisted being moved through something as soft and flexible as muscle. But his body had already been prepped by the Yang chakra. The tissue was denser now, more resistant, and in a strange way, slightly more compatible with the sluggish movement of Earth chakra.

He slowed the flow rate and let the chakra settle gradually, layer by layer.

His muscles tensed again but differently this time. The feedback was like sand being poured into slime. It was gritty, heavy, but not entirely hostile. He had to adjust the flow constantly to prevent clogging or chakra bleeding, but the structure held. And as the chakra settled into place, Ren finally began to understand the basic principle he'd been chasing.

He wasn't trying to coat his body in earth. He wasn't trying to wear armor.

He was embedding chakra into his physical structure using Earth chakra to give that structure density and hardness, and Yang chakra to bind it to the living tissue.

The effect was internal, not external and somehow, it was working.

He flexed his arm again. Still no visible change. But the resistance in the motion was slightly higher. The weight of his limb slightly increased.

He tapped the forearm against the floor lightly, and heard a duller thud than before.

The feeling of that dull thud when he tapped his arm against the floor stayed with him. It was not sharp or crisp like normal it was just heavy and weighted like a hammer striking a surface. The muscle hadn't become rock, but it definitely wasn't soft tissue anymore either.

Ren adjusted his breathing. The second step was to confirm the chakra integration. Right now, Earth and Yang were both inside his muscle structure, but they weren't exactly cooperating.

They were stacked and layered one after the another but they were not merged. He could feel the Earth chakra lying in the muscle like embedded grit, and the Yang chakra trying to keep it from pushing out or damaging the fibers. It was working, technically, but it wasn't fluid. Not yet.

He needed to find a way to combine the two more cleanly. Right now they were existing next to each other, but they needed to function as a single unit, like an alloy, not a sandwich.

He ran a chakra pulse through his right arm again, slowly this time. The Earth chakra clung stubbornly to the tissues it had been forced into, heavy and resistant. The Yang chakra remained more active, flowing and stabilizing, but only within the muscle lines.

It wasn't pushing into the membrane or skin yet, and that meant the structure remained disconnected across layers. If he wanted this to be combat-usable, the durability had to cover not just muscle but the outer body too.

'Maybe I'm doing this backward,' A thought came to him.

He paused his chakra flow and instead focused on creating a mixed chakra stream first. Not Earth and Yang, separately, but a mixed current. His previous experience with chakra combinations told him this wouldn't be an actual elemental fusion.

This wasn't a Kekkei Genkai like Lava Release or Ice Release required advanced genetic traits but mixing two natures without fusing them was something that could still work, like combining Wind chakra with Fire in sequence to increase the damage output of the fire.

Maybe the same applied here.

So, he focused on the ratio. Earth chakra first, slow and steady. A thick current, which was more heavy and grounding. Then, he added Yang chakra, it's quantity slightly more than before and allowed it to flow into the Earth chakra's stream gradually.

The effect wasn't immediate, but it was different. The Earth chakra didn't break apart the moment it met Yang chakra now. It shifted slightly, softened at the edges, almost as if the Yang chakra was lubricating, no, binding it. It was making it more malleable. Instead of trying to force Earth chakra into the muscle, he let the mixed current flow through the tissues in one go.

The difference was clear. There was no scraping or tearing sensation. The chakra flow was smooth and it actually moved.

He traced this new mixed chakra into his right bicep, watching carefully for any signs of strain. None. The flow was steady. He pulsed it slowly into the upper arm, around the elbow joint, then into the forearm again.

When he flexed, the motion felt heavier but natural. Like moving with a training weight, but one fused into the body.

Then he tried something different. He punched downward with just a simple impact against the floor.

The sound was deeper. A bit more forceful than he expected for the amount of motion. and there was a noticeable shock up his arm, it wasn't painful, it was like hitting something with reinforced gloves on.

"That's it," he murmured.

Now the idea was clearer. By mixing the chakra beforehand and guiding it through the tissues as a single infused stream, he could avoid the layering problem. Earth alone made the body stiff. Yang alone just strengthened without durability. But together, in proper ratio and timing, they made the tissues dense, reactive, and semi-armored.

The next step would be reinforcing the outer layer.

The skin.

~~~~~

{Tbh, I was very confused about using the timer for FTG or this hardening so I ultimately spun a wheel and finally decided on hardening.}

{Anyway, this hardening would just be like Kirishima's quirk, only slightly weaker.}

{Also, this idea came from a Patreon member, THEN_XY, though the idea was diferrent, they created the base of using Earth and Yang and create a NOT overpowered Kekaki Genkai which stuck with me, so thanks man or woman, whatever you are.}

{One more thing, fusion implies a merging of distinct entities into a new, unified whole, often involving a more profound and often irreversible change. Mixing, on the other hand, typically refers to the simple combination or intermingling of different components without necessarily resulting in a new, unified substance.}

{If you want, you can support me on pat-reon}

{ h t t p s : / / w w w . p a t r e o n . c o m / Z e e n o n }

{You know what else}

{280 Stones = Extra chapter}

{STONES!!!!}

{Break tomorrow :) }