The prison holding captured Uchiha was one of the most heavily guarded locations within the Senju compound.
Ordinarily, access was tightly restricted.
But Ethan’s status inside the clan had changed completely.
News that he had become a direct disciple of both Hashirama and Tobirama Senju had already spread throughout the compound.
At this point, almost everyone knew his name.
So when Ethan arrived at the prison gates, the guards only performed a routine inspection before letting him pass.
They even assigned an elite Senju shinobi to accompany him for safety.
Still, before opening the gates, one of the guards spoke in a stern voice.
“Do not seriously injure the prisoners.” “Some of them are valuable bargaining chips for future exchanges.” As the war dragged on, both clans had accumulated captives.
Eventually, negotiations would become unavoidable.
Fortunately, Ethan’s experiment posed little danger to the prisoners.
If anything— he was the one taking the real risk.
He nodded casually and stepped into the underground prison.
The moment the iron doors opened, several Uchiha prisoners slowly lifted their heads to look at him.
Only then did Ethan notice the sealing marks wrapped tightly over their eyes.
Specialized suppression seals.
The Senju had developed them through years of bloodshed and experience fighting the Sharingan.
The seals didn’t merely block vision.
They also interfered with Chakra circulation, preventing the prisoners from molding Chakra properly.
If Ethan wanted one of them to use genjutsu— the seals would have to come off first.
He turned toward the accompanying guard.
“Bring me the weakest one.” “The prisoner with the lowest Chakra reserves and the worst injuries.” The guard hesitated immediately.
Ethan smiled reassuringly.
“I just want to experience real Sharingan genjutsu firsthand.” The guard visibly relaxed.
“That’s acceptable.” A few minutes later, the guard dragged out a young Uchiha boy.
Surprisingly— he looked even younger than Ethan.
The boy was painfully thin, pale, and malnourished.
He looked half-dead already.
Even Ethan doubted the kid had enough Chakra left to cast anything significant.
Clearly, prison life hadn’t treated him kindly.
At first, Ethan considered requesting someone else.
But after a moment’s thought, he dismissed the idea.
Better safe than careless.
Without dojutsu or specialized perception abilities, accurately measuring another shinobi’s Chakra reserves was difficult unless the power gap was overwhelming.
For all he knew, the boy could be hiding his condition.
“Be careful,” the guard warned.
Then he reached forward and peeled away the sealing tags covering the prisoner’s eyes.
The instant the seals were removed— the Uchiha boy’s eyes snapped open.
One tomoe in the left eye.
Two tomoe in the right.
The moment their gazes met— Ethan was dragged into an illusion.
Hatred exploded across the boy’s face.
At the same time, Ethan’s expression turned blank and unfocused.
The guard’s breathing hitched.
Instinctively, he prepared to knock the prisoner unconscious.
“Stop.” A deep, calm voice echoed from behind him.
The guard froze immediately before turning around in alarm.
“T-Tobirama-sama!” Tobirama stood near the prison entrance with his arms crossed, watching quietly.
He observed Ethan for a moment before giving a low chuckle.
“The brat’s more cautious than I expected.” “At least he understands how to prepare before stepping into danger.” His eyes narrowed slightly.
“Looks like my brother’s concerns about me being too harsh were unnecessary.” The guard’s heartbeat skipped.
The implication was obvious.
Tobirama wasn’t simply teaching Ethan.
He was grooming him seriously.
As a true successor-level talent.
Before the guard could respond— the young Uchiha suddenly groaned and collapsed unconscious.
At the same moment, clarity returned to Ethan’s eyes.
He inhaled sharply.
A trace of lingering fear still remained on his face.
Even after mentally preparing himself beforehand— real Sharingan genjutsu had been even more dangerous than expected.
Tobirama looked faintly amused.
“You awake?” “How was it?” Ethan immediately straightened respectfully.
“Good morning, sensei.” Then he answered honestly.
“…Terrifying.” His expression became serious.
“It activates too fast.” “I warned myself repeatedly to stay cautious, but I still got caught instantly.” He paused before continuing.
“The worst part is that conventional methods barely work against it.” “You can’t simply disrupt your Chakra flow and break free like ordinary genjutsu.” “You have to overpower it mentally.” “You endure it through sheer will.” Tobirama nodded in approval.
“Correct.” “So far, against elite Sharingan users, the most reliable countermeasure remains simple.” “Don’t look them in the eyes.” Then he added calmly: “Fortunately, genjutsu loses effectiveness on large battlefields.” “War naturally disrupts illusions.” Ethan understood immediately.
“So genjutsu is most dangerous during small engagements or one-on-one combat.” “Exactly.” Tobirama studied him carefully.
“Understand its principles.” “But don’t devote too much time to it.” “It isn’t worth sacrificing your primary training.” Ethan nodded obediently.
“Yes, sensei.” Of course— Tobirama didn’t actually believe he would stop.
The boy clearly had his own plans.
Still, Tobirama said nothing further.
After giving a few final warnings, he turned and left the prison.
The moment he disappeared from sight— Ethan quietly examined his Haki.
And his eyes lit up.
It worked.
The mental pressure generated by Sharingan genjutsu had strengthened his Haki noticeably.
Negative emotions.
Psychological stress.
Mental strain.
All of it forced his spirit to flare outward instinctively.
And Haki itself was manifested spiritual force.
The theory had been proven.
But there was another discovery as well.
As Wood Release continuously enhanced his vitality and cellular activity, his physical constitution improved steadily over time.
And as his body grew stronger— his Haki increased gradually alongside it.
The growth wasn’t nearly as explosive as genjutsu stimulation.
But it was there.
Ethan exhaled slowly, excitement flickering in his eyes.
Then he glanced coldly at the unconscious Uchiha prisoner lying beside him.
“Next.” And just like that— after enduring three separate Sharingan genjutsu sessions— Ethan’s Haki advanced again.
Not only had his Armament Haki strengthened significantly— he had also awakened Observation Haki.