The next day, there were four or five more people in the underground laboratory.
These people were dressed like farmers working the fields, but their faces bore a fierce look, their bodies were robust, and even tied up, their eyes flashed with murderous intent, carrying an aura of violence. Their hands had likely taken more than a few lives.
Hakushi didn't ask where these people had been brought from, nor did he care about their former identities. Odds were, they were bandits who killed and robbed outside.
Right now, the chaos outside bred countless marauding bandits. Hakushi had run into such things before while out on missions, and had conveniently dealt with more than a few gangs.
But at this moment, Hakushi wouldn't bother where they came from or what they did. Once they entered this lab, their fate was like the white mice he'd handled previously—mere experimental subjects.
With a systematic plan, the Natural Energy experiments themselves carried no fatal risks, but nothing's ever absolute. Previously he'd experimented on animals, whose life structures differ greatly from humans, so now that he's using humans for Natural Energy injection experiments, there's always the possibility of unforeseen dangers.
"Test subjects are hard to come by—don't waste them all at once."
Ruri said this as she was leaving.
It had taken considerable manpower and resources to transport these subjects here, so she made a point to remind him.
"Relax. Don't forget I'm a Medical Ninja—I can recycle them again and again."
Hakushi understood well enough how hard it was for Ruri to procure these subjects, so he wasn't planning to burn through them all at once.
Medical Ninjutsu was especially useful now. As long as they didn't die, he could reuse them as often as needed.
Besides, Hakushi figured his research posed very little risk to life. Before moving on to human trials, he'd already done extensive animal testing. As long as he was careful, their lives were basically guaranteed.
Once Ruri left, Hakushi shifted into work mode.
The people brought over had their mouths sealed with cloth so they couldn't shout, just low muffled sounds of anger—clearly not pleased with their treatment.
For bandits living life on a knife's edge, fear wasn't even in their eyes; probably all they were thinking about was how to kill Hakushi and escape.
Hakushi ignored their low growling. He picked one at random, lay him down on the experimental table. The guy was too unruly, so Hakushi injected him with half a vial of anesthetic, making him sluggish and finally quiet.
"Relax. Serving as my test subject here, you'll have food and water, nothing lacking—better than licking blood off knives outside, never knowing when you'll suddenly die. And my experiments basically carry no danger to life—I can guarantee you that much."
Their mood seemed to shift; their eyes darted, while Hakushi's tone stayed calm and even.
For sustainable use, Hakushi would do his best to keep their lives intact.
After all, in times like these, most people lived day-to-day just for a mouthful of food.
Big countries were better off, but in smaller nations, even a single meal was a luxury; people gnawed wild plants at the roadside, maybe not even that.
In this war-torn age where morality and ethics meant little, Hakushi had long taught himself that life wasn't worth celebrating, and death wasn't worth mourning.
Life was, more often than not, priceless—because it was worth nothing.
◎
Two days later.
Hakushi emerged from the underground lab; for those two days, aside from eating and sleeping outside, he spent most of his time submerged in experiments below.
Though there wasn't much progress yet, considering human trials had just started, at least a week of observation was needed before drawing any conclusions.
After leaving the lab, Hakushi took a breather.
It was already July, and the sunlight felt scorching, as if the sun was draining away all his energy.
What always made Hakushi want to complain was, this world had electric lights and computers—so why no air conditioning?
He headed to Ruri's room, where it was refreshingly cool—a world away from the muggy heat outside.
The room was packed with ice blocks and fans blowing nonstop, spreading the cold evenly to every corner, creating an effect just like air conditioning.
Ruri was dressed in a loose blue casual outfit, surrounded by scattered scrolls and black suitcases.
"What's this?"
Hakushi pointed at the scrolls and cases.
"The reward from our previous mission—this is your share. Total cash: 1.2 million ryo. The rest are scrolls on medical knowledge, plus a few pretty practical Medical Ninjutsu techniques."
"Oh, I see." Hakushi sat down, opened one of the scrolls, and immediately grinned. "Didn't expect the village to be so generous, rewarding me with something so precious. These are exactly the resources I was hoping for. I thought they'd just toss me whatever and call it done. Guess the higher-ups at the village aren't totally heartless after all."
"It's precisely because they want to brush you off that they gave you these, dumbass. Is that all you aspire to?"
Ruri shot Hakushi a disdainful look as he basked in smug satisfaction.
"???"
"For them, dispensing with you using these is the most convenient and least resource-intensive option."
Upon hearing this, Hakushi immediately figured it out.
"Doesn't matter—even if by accident, these materials and Medical Ninjutsu are genuinely useful for me."
"Really? As long as you're happy."
"By the way, what about your reward, Ruri?"
"I'll be heading to the Hokage Building soon. The village leadership has approved me to pick any Ninja Technique I want from the Sealing Book."
Ruri's expression was one of real surprise as she said this.
It seemed even she hadn't expected the Third Hokage to show such boldness.
As far as she knew, the Senju line and their Uchiha Clan had always been on bad terms; even if things had eased in recent years, it was only a surface-level friendship.
Hearing this, Hakushi suddenly felt the scroll in his hand wasn't so exciting anymore.
"Have you decided which Ninja Technique to pick?"
Hakushi collected himself and asked.
Ruri yawned in boredom, flopped onto her side, and toyed with a Kunai in her hand.
"The elders of the clan respect my choice, but I don't really know which Ninja Techniques in the Sealing Book are actually powerful, and frankly I don't lack high-level techniques, so I haven't decided yet. Any suggestions?"
Ruri had some understanding of the Sealing Book, but she wasn't exactly certain how many Forbidden Techniques, ultimate moves, and secret skills were documented, or what varieties.
"How about something related to the soul?"
Hakushi suggested.
"Soul?"
Ruri raised her eyebrow.
"I heard there's a Jonin in the village named Katou Dan, who uses a rather mysterious soul-type Ninja Technique. He's apparently Tsunade-sensei's boyfriend. This kind of technique would really help my research, I think."
"Got it."
Ruri thought for a moment, then nodded agreement.
She had no strong need for a Ninja Technique from the Sealing Book anyway. If a soul-style technique could genuinely help Hakushi uncover the secrets of Immortal Technique sooner, that'd be a massive boost for her as well.