Byakugan

Over the past half-month, Hyuuga Nen had been training with Kuromaru, and through these sessions, his practical combat experience had improved significantly.

During this time, Hyuuga Nen also mastered a small technique recorded within the Seal of Resilience his father had left behind. Through this, he could open and close the seal on his Byakugan, as well as provide the necessary chakra to maintain the sealing technique.

Today, with Kuromaru's assistance, Hyuuga Nen would attempt to unlock the seal on his Byakugan for the first time.

"Are you ready? Although your father's sealing technique is quite mature, this is the first time he has applied it to a Byakugan. I'm not entirely sure what the consequences of breaking the seal might be," Kuromaru said, watching Hyuuga Nen with a hint of nervousness.

"What must come will come. I can't run away from it, can I?" Hyuuga Nen was actually quite nervous himself, but he feigned a relaxed tone.

"Then let's begin." With that, Kuromaru sat down in front of Hyuuga Nen, staring at him intently.

Hyuuga Nen took a deep breath and sat on the ground. He gathered the chakra within his body, formed a complex set of hand seals, and slowly placed his index and middle fingers on both sides of his forehead.

"Seal, release!" Hyuuga Nen whispered.

He slowly lowered his hands while sensing the changes in his eyes. Black runes began to emerge from his temples, slowly extending toward the corners of his eyes. They surged and pulsed, as if trying to break free from his body.

Hyuuga Nen took out a prepared mirror and, using the reflection of the moonlight and the snow, carefully observed the changes. In the reflection, the black runes gradually stopped pulsing, their color fading until they vanished entirely.

Simultaneously, the color of Hyuuga Nen's eyes faded as well, eventually turning a pale, deathly white—exactly like the Byakugan he remembered.

"This is the Byakugan!" Hyuuga Nen gently touched the corners of his eyes. He stood up and looked around.

"I feel like the surroundings have become a bit brighter. So, the Byakugan has night vision?" Hyuuga Nen remarked while observing his surroundings.

"Alright, now try to activate your ocular powers," Kuromaru instructed.

Hearing this, Hyuuga Nen nodded and began to form hand seals. Since it was his first time, he still needed the assistance of the seals.

"Byakugan, activate!" As chakra surged toward the corners of his eyes, veins began to bulge around them, giving his face a somewhat ferocious appearance.

Once activated, Hyuuga Nen clearly felt that the world had changed. Just as he was preparing to examine the differences, a massive wave of pain erupted in his eyes—a pain so intense it felt as if it were piercing deep into his brain.

"Aaaah!"

The agony rendered Hyuuga Nen speechless, leaving him only able to let out screams. He reached up to clutch his eyes, but then collapsed straight to the ground, writhing in pain.

"Damn it, the worst-case scenario has happened!" Seeing Hyuuga Nen's wretched state, Kuromaru immediately rushed to his side. However, Kuromaru was helpless against the situation and could only pace anxiously around him.

By the time Kuromaru noticed Hyuuga Nen had stopped rolling and had fallen unconscious, blood was slowly streaming from his wide-open eyes. Unable to worry about anything else, Kuromaru grabbed Hyuuga Nen's clothes in his mouth and ran quickly toward his house.

Hyuuga Nen woke up. He reached for his eyes and discovered they were wrapped in bandages. Feeling a surge of panic, he pulled back a corner of the dressing.

Upon encountering the light, his eyes stung, but his heart settled; in that brief moment, he had caught a blurry glimpse of his surroundings.

"At least I'm not blind," Hyuuga Nen said, re-securing the bandage with a sigh of relief.

"You're awake. How do you feel?" He heard Kuromaru's voice.

"My eyes aren't blind, but I can't handle light for the time being."

"Hmm, it's not the worst-case scenario. Rest for a while. I will monitor your condition. If things take a turn for the worse, I'll have to take the risk and use a reverse summoning to bring your father here."

Hyuuga Nen was in no mood to respond and simply gave a faint grunt.

Hyuuga Nen rested for two weeks. During this time, he hid in his room, refusing to go anywhere to prevent others from noticing anything amiss. Rika also announced to the outside world that her son was ill and needed to rest, unable to see anyone.

During his recovery, Hyuuga Nen couldn't train with Kuromaru, so he used Shadow Clones to spar instead. Once the clones dissipated, the experience was transferred back to him. Due to the limitations of the clones' strength, the training intensity was lower than before, but it was better than nothing.

Two weeks later, Hyuuga Nen's eyes had fully recovered. Activating them again caused no discomfort, and only then did he finally set his mind at ease.

Today was Kuromaru's last day here, and Hyuuga Nen personally conducted one final training session with him.

After pointing out Hyuuga Nen's shortcomings, Kuromaru provided guidance on his cultivation. Since Hyuuga Nen had been training alone, errors and oversights were inevitable, and through Kuromaru's instruction, he was able to correct his path.

"I've explained my mother's situation to you. I need more advanced medical ninjutsu, especially the Extraction of Malady Technique. Can you get it for me?" Hyuuga Nen asked.

Kuromaru was silent for a moment before nodding. "Your father bears some responsibility for your mother's current state. I will tell him and do my best to get you what you need, though it may take some time."

Hyuuga Nen simply nodded, saying nothing more.

Seeing that Hyuuga Nen had nothing left to say, Kuromaru turned and left.

"Now, it's time to fully test the capabilities of the Byakugan." With that, Hyuuga Nen activated his eyes.

In the darkness of the night, he strained his vision to look into the distance. He could see objects several kilometers away with absolute clarity. Whether large or small, every detail was laid bare before his eyes. By adjusting his perspective, he could even look through obstacles to see his targets.

"Is this the power of the Byakugan?" He shifted his gaze to the ground, intending to see what lay beneath, but found only pitch blackness.

"Hmm, why is that?" He pondered for a moment, then slowly formed a seal. Five earthen walls rose up around him, enclosing him completely.

Inside the walls, Hyuuga Nen could no longer see the outside world. "It seems that even with the Byakugan, I cannot see anything in total darkness," he concluded.

He then performed the Shadow Clone Technique, having his clone use Earth Style to burrow underground. To his surprise, he could see the clone moving slowly beneath the surface.

"What does this mean? Does chakra emit light?"

Hyuuga Nen questioned himself. He then realized that while he couldn't see outside the earthen walls, he could see his own chakra flow, his meridians, and his acupoints.

"Chakra truly is miraculous," he marveled.

By the time the clone had reached a depth of ten meters, Hyuuga Nen lost track of it and dispelled the technique.

"It seems that even with a chakra signature, I can only see about ten meters underground for now. I wonder if I can see further as the Byakugan improves?" He rubbed his chin, deep in thought.

"There is no doubt that the Byakugan's observational power is exceptional, but it is not without limits. In places without light or chakra, it is no different from being blind. If an enemy were to lurk underground outside my field of vision, I wouldn't be able to detect them. I must be especially careful of this, or I could easily be ambushed."

Having reached his conclusion, Hyuuga Nen did not deactivate his Byakugan, but continued his testing to see if he could make further discoveries to better master his new ability.