The treatment continued for quite a while. When the green light at Tsunade's fingertips slowly faded, the hideous and terrifying wound on Shinichi's right arm had disappeared.
The new skin still had a faint pink tint, and the muscle texture had been restored to its original state. Although it was still weak and required a long period of rest to regain its function, the constant erosive sensation of destruction and the bizarre nature of the injury had been completely purged.
"The toxins in the wound have been cleaned out, and the basic repairs are finished. The rest depends on your own recovery. With your constitution, you should be able to move around after lying down for half a month. However, remember, you are not allowed to perform any high-intensity ninjutsu practice or taijutsu training within a month. Otherwise, you'll leave behind internal injuries that will give you a hard time on rainy days."
Tsunade withdrew her hand, her face still somewhat pale and her forehead wet with sweat, but her eyes were much clearer than when she arrived. After finishing her piece, she didn't even look at Shinichi before turning around and walking toward the door.
Opening the door, Tsunade paused for a moment when she saw the Third Hokage and Enma at the entrance.
"Old man," she greeted him. Her tone was flat, devoid of any discernible emotion.
"Thank you for your hard work, Tsunade," the Third Hokage said gently, his gaze lingering for a moment on her still-pale face with concern.
Tsunade avoided his gaze and simply waved her hand, heading straight toward the other end of the corridor. Her back was straight and her pace was fast, as if she were in a hurry to leave this place.
The Third Hokage watched her leave until her long blonde hair disappeared around the corner, then he retracted his gaze and looked back into the hospital room.
On the hospital bed, Shinichi was trying to gently move the fingers of his newly healed right hand. There was no particular expression on his face—neither the relief of surviving a disaster nor worry about his injuries. He was as calm as a youth who hadn't just recovered from a serious wound.
"How do you feel, Shinichi?" The Third Hokage walked into the room, his voice steady.
"Much better, Lord Hokage. Thanks to Lady Tsunade," Shinichi replied politely, his tone respectful.
The Third Hokage nodded and sat down on the chair by the bed. After a moment of silence, he slowly spoke: "Regarding this new technique you developed, the FireStyle: Rasengan, Enma has already told me in detail. Its power is astonishing, but the risk is also immense. Until you find a way to fully master it or eliminate its backlash, I do not allow you to use it lightly again. This is not a suggestion, it is an order! Your future is more important than an incomplete technique, do you understand?"
Shinichi met the Third Hokage's serious gaze, remained silent for a few seconds, and then slowly nodded: "Yes, I understand, Lord Hokage."
His obedience was without hesitation, but from the depths of those calm eyes, the Third Hokage saw a flicker of a flame that had not been extinguished.
He knew that this boy's understanding might only be a temporary dormancy.
After a few more words of advice to rest and recover, the Third Hokage stood up and left.
As the Hokage, he still had too many matters to attend to.
Quiet returned to the hospital room. Shinichi leaned against the headboard, looking at the snowflakes beginning to fall outside the window, his thoughts unknown.
---
Half a month later, midwinter.
At Konoha's Fourth Training Ground, the snow had not yet melted, and the air was cold and crisp.
Enma stood with arms crossed, looking helplessly at the black-haired youth in the center of the field who was warming up his limbs, his aura already steady.
Beside him, the Third Hokage Sarutobi Hiruzen, draped in his Hokage robes, also stood there quietly, his gaze gentle yet scrutinizing.
Shinichi's recovery speed had exceeded Tsunade's expectations. As soon as his injuries stabilized, he couldn't wait to throw himself back into training.
After first conducting a practice session of taijutsu and ninjutsu transitions with Enma at a controlled intensity, he began to try out his ideas for perfecting the Fire style: Rasengan.
Enma knew well the danger of that technique's backlash and couldn't dissuade him, so it simply invited the Third Hokage over, who happened to be resting as his recent affairs had slowed down.
With the Third Hokage present, at least there was someone to handle any emergencies.
"Shinichi." The Third Hokage looked at the youth who approached. He didn't give a direct order or reprimand, but instead asked peacefully, like a mentor guiding a disciple's thinking: "In such a hurry to try again, have you thought of a way to solve the backlash problem?"
"Yes, Lord Third Hokage." Shinichi bowed respectfully and then nodded frankly. "During this half month, I have repeatedly recalled the details of when I was injured and summarized the cause. The Rasengan itself is a highly compressed and violently rotating sphere of chakra, which is inherently unstable."
"The Fire style: Rasengan forcibly injected fire-nature chakra, which is known for its volatility. When the two are combined, the power is doubled, but the internal energy also becomes extremely violent. At the moment of hitting the target and releasing the energy, that violent feedback directly impacts the arm of the user who is maintaining the chakra form, causing severe erosion and tearing."
He paused and continued: "So, the simplest idea is—don't let it explode directly in my hand. If I can throw it safely like I use a kunai or shuriken, making it explode far away from me, then the problem of backlash will be solved."
The Third Hokage nodded slightly. "Throwing it to avoid direct contact damage is indeed a correct direction. It's one of the conventional ideas for solving the backlash of such close-range explosive ninjutsu."
But he changed the subject and pointed out the key difficulty: "However, Shinichi, the problem lies in throwing it safely. An ordinary Rasengan is already difficult to maintain its form after leaving the body, let alone the extremely unstable Fire style: Rasengan with violent fire attributes injected? It's like a piece of dynamite with a lit fuse that is extremely sensitive. You still need to put all your effort into maintaining it in your hand so it doesn't explode prematurely. Once it leaves your hand, I'm afraid as soon as it loses your continuous chakra control and form maintenance, it will explode on the spot due to losing control."
Enma said in a deep voice from the side: "Hiruzen is right. Kid, the idea is good, but it's too difficult to do. Once that thing leaves your hand, it's a firecracker that goes off at the slightest touch. It won't fly far at all."
"Yes, Lord Third Hokage, Enma-san, I have also repeatedly thought through this problem."
Facing the core dilemma pointed out by the Third Hokage and Enma, Shinichi did not show discouragement or confusion. Instead, he nodded:
"Because of this, I thought of another approach. Since the backlash of the Fire style: Rasengan stems from the combination of its extreme compression, rotation, and violent fire attribute, which makes the explosion of this technique difficult to control and extremely unstable... then, can we take a step back? We could keep the core advantages of the Rasengan's speed and high concentration of chakra, but appropriately reduce the degree of concentration, while completely removing the rotation characteristic that exacerbates the instability?"
"Like this!"
Before his voice had even faded, he had already raised his right hand, his five fingers slightly spread.
There were no complex hand seals, and not even any obvious violent fluctuations of chakra. A ball of blazing and solid crimson flame, as if tamed by an invisible force, suddenly appeared on his palm!
This flame did not expand outward like an ordinary fire release, nor did it rotate violently and compress to the extreme like the Great Flame Rasengan.
It was more like a highly concentrated core of flame that had been stripped of excess turbulence, appearing as a stable, solid-like core. It burned quietly, emitting intense but not disordered energy fluctuations.