Inside a hidden underground chamber, the few medical-nin still left on Sunagakure's side were struggling to keep up with the endless tide of wounded being carried in from the battlefield.
There had originally been seven of them. Now only three remained.
Their healing strength had been cut down drastically, and among those three, Yubi was the youngest by far. Even so, he had somehow become the de facto leader of the entire medical team.
Whenever the other two medical-nin ran into a case they could not handle, they would call for him almost on instinct.
Despite the urgency, Yubi's hands never lost their rhythm. He categorized the wounded by severity, had the lightly injured treated first, and directed the people inside the base like a seasoned field commander.
Some of the shinobi who had lost the ability to fight but could still move served as assistants, carrying supplies, holding patients down, and cleaning blood from the floor before it turned the whole chamber into a slaughterhouse.
For the moment, under Yubi's management, the chaos was barely being kept under control.
By now, the battle raging through the canyon had already reached a white-hot pitch. Commander Takuma had issued a strict order: none of the three remaining medical-nin were allowed to go back outside.
They were too important. Yubi especially.
If anything happened to him, the casualties on the battlefield would likely double in an instant. The consequences would be unthinkable.
"Hold on a little longer... the village's reinforcements will be here soon."
In the underground chamber, wounded Sand shinobi encouraged one another through clenched teeth and bloodstained smiles. Some of those with lighter wounds rested only briefly before forcing themselves back to their feet and staggering toward the surface again.
All they needed to do now was hold out. Just hold out a little longer.
A moment later, a Sunagakure Chunin hurried over. He saw Yubi kneeling beside a patient, one hand glowing green with the Palm Healing Technique, and his expression unconsciously turned respectful.
"Yubi... Commander Takuma asked me to pass on a message. If you're not feeling well, don't force yourself. You're extremely important to us."
"I'm fine," Yubi replied with a small smile.
It was already the second night. The clash between Sunagakure and Amegakure had lasted a full day and night, and during that entire stretch, Yubi had not slept for even a moment.
He had already exchanged for both the Palm Healing Technique and the Chakra Scalpel. But because his chakra reserves were still too limited, he had never used the Chakra Scalpel in battle. He conserved every drop he had and relied on his real scalpel for incisions instead.
Fortunately, he had long since noticed something important: as his physical condition improved, the speed of his chakra recovery improved with it.
Chakra was, in the simplest sense, the fusion of spiritual energy and physical energy. That meant the body mattered just as much as the mind.
Still, the Palm Healing Technique was an A-rank medical ninjutsu. The chakra consumption was far more brutal than Yubi had expected.
With his current reserves, healing two seriously wounded people at the same time was already pushing him toward collapse. Their injuries were too severe, and stimulating cell regeneration on that level demanded an enormous amount of precise chakra control.
That, more than anything else, made him understand how important chakra quantity was for a ninja.
If he had the chakra reserves of a tailed beast, healing this roomful of people would probably feel as easy as breathing.
The Chunin messenger lingered there for a second, clearly wanting to ask something, then swallowed it.
The boy in front of him had already earned the respect of everyone present through sheer ability. At first, most of them had only thought Yubi was a child with unusually solid medical fundamentals.
None of them had imagined that a fresh Academy graduate could actually use the Palm Healing Technique.
Even within the whole of Sunagakure, not many people were capable of performing a medical ninjutsu of that level. Chiyo herself was the clearest example of what a true medical expert looked like.
And the Ninja Academy certainly did not teach techniques like this. The village would only begin that sort of training after confirming that someone had the aptitude to become a medical ninja.
Which made Yubi's existence all the more startling.
No one dared ask how he had learned it in the middle of a war, but the thought lingered in almost every mind in the room.
Without Yubi, this frontline position would probably have collapsed by now.
Compared to him, the other two medical-nin seemed almost ordinary. Useful, yes, but ordinary.
If not for this boy keeping the less severely injured alive, patched up, and able to return to battle, Amegakure would likely have smashed straight through Sunagakure's defense line already.
A genius.
A true medical genius.
That idea had quietly taken root in everyone's heart.
For Sunagakure, the appearance of a talented medical ninja in the middle of a war was undeniably good news. The Second Shinobi World War was not over yet, and Konoha was producing one rising force after another.
Naturally, Sunagakure could not afford to fall behind.
To the village, Sasori was already a priceless treasure. But Yubi... Yubi felt like a gem they had stumbled across by sheer luck.
News from the border battlefield had almost certainly already reached the village by now. Which meant the higher-ups had probably also heard about Yubi's performance.
...
In truth, Yubi was exhausted.
He wanted nothing more than to find a corner, collapse, and sleep like the dead. His eyes were bloodshot, and his footsteps had already begun to drift. He knew his own state better than anyone.
But the reason he kept going was not some noble sense of duty, nor was it loyalty to the village.
In his eyes, the wounded all around him were walking bundles of precious experience points.
It would be absurd not to harvest them.
This border conflict was a rare chance for him to grow stronger at an explosive pace. Once the battle ended, who knew when another opportunity like this would appear?
"Make way!"
Just then, a Sand shinobi carrying someone on his back rushed into the underground base, sweat running down his brow. His eyes swept across the room and immediately locked onto Yubi.
The atmosphere instantly shifted.
The moment people recognized the figure being carried in, a wave of unrest spread through the chamber.
Because the person on that shinobi's back was none other than Sasori.
"What happened?" someone asked at once.
"An Amegakure Jonin..." the man replied in a heavy voice.
The later waves of Amegakure shinobi that had infiltrated the canyon were not especially powerful on average, but they were numerous. Just like Sunagakure's side, they naturally had key fighters and battlefield commanders among them.
People like Takuma. At minimum, Jonin-level figures.
And while standards varied from village to village, a Jonin was still a Jonin. Even if their overall strength was inferior to the elites of a Great Ninja Village, they were not opponents ordinary shinobi could casually defeat.
Sasori was a genius puppeteer, yes. His talent was undeniable. But after fighting continuously for so long, running into a Jonin-level enemy at that point was almost the worst possible matchup.
The fact that he had survived at all already bordered on a miracle.
Yubi understood this better than most. The enemies he had dealt with were nowhere near the same level as the ones Sasori had been handling.
Sasori's targets had largely been Amegakure elites.
"Lord Takuma stepped in to protect him..." the shinobi carrying him added, then hesitated, as if there were more he wanted to say.
Yubi said nothing. He immediately moved over and began checking Sasori's condition.
His fingers were quick and steady. Pulse. Breathing. Bleeding. Fractures. Internal trauma.
After confirming that Sasori was wounded but not fatally so, Yubi finally let out a silent breath of relief.
He did not actually know whether this clash between Amegakure and Sunagakure at the border had happened in the original timeline of the Second Shinobi World War. He knew the broad outline - that Amegakure, Sunagakure, and Konoha had all been central forces in this war - but he did not know the details of every single battlefield.
Logically speaking, if Sasori had taken part in a war like this, he should have survived. But what if Yubi's existence had already altered the flow of events? What if the butterfly effect had started spreading farther than he realized?
That would be a real problem.
Because in Yubi's eyes, Sasori was not just a classmate or a genius.
He was one of Sunagakure's future pillars.
More than that, he was an essential piece in Yubi's long-term plan to reshape the village's fate. For that reason alone, absolutely nothing could be allowed to happen to him.
"It's fine..." Yubi murmured, more to himself than anyone else, as he began treating Sasori's wounds.
He worked carefully. Cleaned the wounds. Stopped the bleeding. Stabilized the damaged areas. Then he guided the Palm Healing Technique into the places that needed it most, avoiding any unnecessary waste of chakra.
Even exhausted to this degree, his control was still frighteningly precise.
Then the familiar system notification rang out inside his mind.
Ding! Host has successfully healed a story character. This is the first time the host has healed this character, unlocking a character-related bonus. Experience gained: +200!
Yubi's hand froze for the briefest instant.
His eyes narrowed.
He had heard all kinds of notifications from the system before, but this one was new.
A story character? A first-time heal bonus?
For the first time since the battle had begun, genuine surprise flashed across his tired face.
"...Huh?"