As anticipated, the aging agent developed by Tsunade took effect, stimulating rapid cell division that spread from the severed tail to the demon's main body, causing its cells to begin dividing rapidly as well.
Swish.
The mechanism activated, instantly severing the artificial blood vessel connecting the tail to the body.
Tsunade ordered, "Report data in real-time!"
Yakumo shouted, "The test subject's cell division is still accelerating, surpassing 1700%! The aging agent's effects are still active!"
A medical ninja monitoring the demon's body reported, "After the severance, the 'monster's' data is starting to stabilize."
Not all demon flesh could function independently from the body.
For the demon in the lab, once a limb was detached, it would wither rapidly like a flower under scorching sunlight. Thus, after the artificial blood vessel was cut, the severed tail quickly shriveled, losing its value for further observation.
After compiling the experiment's data, the research team convened a meeting.
Tsunade spoke first, "Based on this experiment's data, our direction in developing the aging agent is undoubtedly correct!"
"Fantastic!"
The team erupted in cheers.
The pharmacology experts specially recruited for the project beamed with joy.
Tsunade raised a hand, signaling for quiet, then continued, "While this experiment confirmed the aging agent's effectiveness, its current potency is suboptimal. It's unlikely to deliver a decisive blow in combat. We need to keep enhancing its strength!"
The team nodded in agreement.
From the experiment, the aging agent's peak potency, combined with the energy loss from cellular aging, caused a demon to age roughly ten to twenty years in a minute.
For a normal human, that was nearly half a lifetime.
But for demons with rapid regeneration, this only weakened them to a degree, far from being lethal.
A senior medical ninja raised a hand. "Lady Tsunade, regarding improvements to the aging agent, our pharmacology team has new ideas. We estimate the Type-2 aging agent could be at least ten times more potent than Type-1."
Another medical ninja added, "We can also refine the injection method to increase instantaneous delivery, boosting the dosage per unit by over three times."
Tsunade nodded slightly. "Excellent. Begin improvements immediately!"
Shizune interjected, "Lady Tsunade, continuing to test on detached limbs may not allow us to gauge the aging agent's maximum potency!"
Her words drew everyone's eyes to the demon chained in the lab's center.
Testing on a limb couldn't fully measure the agent's weakening effect on a demon. True data required testing directly on the demon itself.
However, the village had gone to great lengths to capture this single demon. If it were accidentally killed, many subsequent experiments would grind to a halt.
Though Shizune's point was valid, Tsunade could only shake her head helplessly. "The 'monster' holds too many secrets. We can't risk testing the aging agent directly on it, as that could result in losing the test subject entirely."
Shinji, attending the meeting, smirked inwardly.
The lack of test subjects was indeed a major issue for the research team, but for Shinji, it was no problem at all.
However, he wasn't in a rush. The Type-1 aging agent's potency was far too weak, only marginally weakening ordinary demons. Against the Demon King, or even Upper String demons, it would likely be ineffective.
What Shinji needed was an aging agent capable of comprehensively debilitating the mysterious figure wielding 'Demon King Power.'
A week passed in a flash.
During this time, Shinji's various plans progressed steadily.
Seizing an opportunity, he extracted Sasuke's chakra once more to ensure the Eternal Mangekyo Sharingan in Karin's eyes continued to be nourished by All Creation Power.
The Tenseigan chakra absorbed from the moon had been fully sealed into the half 'biological exoskeleton' in Neji through multiple absorption sessions.
As for Tsunade's research team, the pharmacology unit worked overtime and completed the development of the Type-2 aging agent.
However, with no new demons captured and no suitable test subjects, potency testing for the Type-2 agent was temporarily delayed.
Outside Hidden Leaf Village.
Under moonlight, Ryuzetsu met Karin at their usual rendezvous point, reporting the week's intelligence gathered by Hidden Grass Village. "Leader, various factions are secretly hunting 'Upper String' monsters. Rumor has it some have been captured and sold on the black market."
Karin frowned slightly.
As Shinji's 'attendant,' she was aware of the contamination demons carried. Though Shinji had explained that the contamination was now impossible to eliminate, hearing that demons were being pursued by various factions still made her instinctively uneasy.
Ryuzetsu continued, "There's a rumor that Hidden Rock discovered traces of 'Upper String Two' and launched a suppression operation."
Karin asked, "And then?"
Ryuzetsu shook her head. "No further news. Hidden Rock is tight-lipped about the battle. From reports by our newly planted spies in Hidden Rock, they recently disbursed a substantial condolence payment, but no other details have emerged."
"Alright, you can go."
After dismissing Ryuzetsu, Karin promptly relayed the information to Shinji.
Shinji shook his head upon hearing the news.
Hidden Rock's operation against 'Upper String Two' had clearly failed.
Shinobi were adapting to demons, but demons were also adapting to shinobi. Especially elites like 'Upper String One' and 'Upper String Two,' who were master swordsmen before becoming demons, had honed their Breathing Techniques to extraordinary levels, capable of unleashing their full physical potential. Even without their near-immortal demonic bodies, they were formidable.
As demons, they were virtually flesh-forged killing machines. Eliminating such demons was no easy task.
Karin requested, "Leader, let me take action!"
Shinji waved a hand. "No rush. These demons are still useful to me!"