The Problem of the Byakugan

After Mizuki returned, Riyue could once again head over to her place every day to freeload meals. Mizuki also decided to guide Riyue's training, passing down the techniques of the Gentle Fist and the Byakugan.

Having a deep understanding of the Naruto world, Riyue knew that the Byakugan was a kekkei genkai possessed by the Hyuga Clan. It originated from Kaguya Otsutsuki, the mother of the Sage of Six Paths. Her younger son, Hamura Otsutsuki, inherited her Byakugan and later became the patriarch of the Otsutsuki Clan, taking the entire family to the moon. The Hyuga Clan were the descendants Hamura left behind on Earth, inheriting his sage eyes—the Byakugan—though, unfortunately, they did not inherit his sage body.

The Byakugan's observational prowess is astonishing, possessing ultra-long-range vision that allows the user to see things over a kilometer away. It grants a 360-degree field of vision; the main branch's Byakugan can perceive the entire surrounding space, but the branch family's Byakugan has a blind spot due to the Caged Bird seal—a one-degree blind spot that spreads outward from the direct rear of the first thoracic vertebra.

The Byakugan also possesses powerful X-ray vision. By using it, one can see a target's meridian system and the flow of chakra, thereby determining the opponent's chakra levels, predicting what ninjutsu they might use, and even identifying whose chakra it is.

Another advantage of the Byakugan is that it is easy to awaken; any Hyuga ninja can do it. Furthermore, members of the Hyuga Clan with the Byakugan can release chakra from any tenketsu on their body, a feat ordinary ninjas cannot achieve.

Of course, the advantages of the Byakugan only hold up against ordinary ninjas. Since chakra does not fall into the five basic elemental categories, the Hyuga family cannot use the five great elemental releases. If they encounter a master, even if the opponent lacks a kekkei genkai, the Byakugan does not offer much of an edge. Try dealing with the Hidden Mist's Water Release, the Uchiha's Fire Release, the Hidden Cloud's Lightning Release, the Hidden Stone's Earth Release, the Hidden Sand's Wind Release, or any of the other endless abilities—each one is enough to give a Byakugan user a headache. The role of Hyuga ninjas has largely been relegated to team support and reconnaissance.

"Riyue, to activate the Byakugan, you must first channel chakra through your meridians to your eyes, like this." Mizuki formed a few hand seals in front of her chest. "Byakugan!" A surge of pressure radiated from the center of her brow, and her eyes turned a pale, bluish-white. Veins bulged around her eyes, and a circle of black markings and patterns appeared within her pupils. Everything within her line of sight was laid bare before her.

The Byakugan really isn't very aesthetically pleasing when activated, Riyue thought.

Mizuki stopped channeling chakra, her eyes returning to normal as she continued, "Of course, once you are proficient with the Byakugan, you can activate it without hand seals. Like this." The veins around her eyes bulged again, chakra surged into her Byakugan, and the black patterns reappeared in her pupils.

Then, Mizuki explained the hand seals for activation, which meridians and tenketsu to channel chakra through to reach the eyes, the amount of chakra required, and several precautions.

Following Mizuki's instructions, Riyue began to attempt the hand seals, then channeled chakra to his eyes.

"Byakugan!" Riyue instantly felt the veins around his eyes bulge, and a circle of pressure emanated outward. Looking around, everything felt different; the world turned monochrome and transparent. Riyue could see things behind him without turning his head, as well as the flow of chakra within Mizuki's body. He could even see the flowers and grass behind her clearly, his vision piercing through layers of trees and picking up minute details.

Riyue discovered that he could see everything within a 100-meter radius clearly; not a single rustle of grass escaped his eyes. By focusing slightly, he could see the texture of a tree in the distance as if he were standing right in front of it, staring at it. Beyond 100 meters, things became less clear, he couldn't see as microscopically, and he lost the ability to see through objects. The further away he looked, the fewer details he could see, until after 500 meters, it felt like normal vision.

It seems my current effective range for the Byakugan is 100 meters, barely pushing to 500, Riyue thought. This means within 500 meters, I see more clearly than the average person, but beyond 500 meters, it has no effect. It's like having X-ray vision and a magnifying glass for 100 meters, and a telescope for 500. I need to train my Byakugan well; I want to be able to see beyond the normal human visual range in the future.

Hmm! This feels good. I've practiced my chakra control for a long time, let's see if I can activate it without hand seals, Riyue thought, and deactivated the Byakugan.

Riyue then attempted to control his chakra flow, slowly channeling it into his Byakugan without forming any seals. The veins at the corners of his eyes bulged once more, and the Byakugan activated again.

"Riyue, you activated the Byakugan without hand seals?" Mizuki stared at Riyue's eyes, stunned.

"Yeah, Mizuki-jie, it's still a bit difficult, though," Riyue said with a smile and a nod.

"Others have to practice for a long time before they can activate the Byakugan without seals, and you can do it right from the start..." Mizuki was shocked by Riyue's talent.

"Uh? Is that so? Is activating the Byakugan without seals really that hard?" Riyue asked.

Mizuki nodded. "It took me half a year of practice to activate the Byakugan without seals... Riyue, are you actually a genius?"

"Uh~~~ it's not that exaggerated. I've just been practicing my chakra control very diligently," Riyue said, scratching his head in embarrassment.

Just then, Riyue's Byakugan faded naturally, returning to its original state.

"Hm? What's going on?" Riyue realized his chakra had been almost completely exhausted.

Riyue was startled. This—this Byakugan consumes way too much chakra, doesn't it? It's only been five minutes, and I haven't done anything else, yet my chakra is already drained! How do Neji and Hinata manage to fight while keeping it active? Isn't the chakra consumption for the Byakugan supposed to be very low?

"Riyue, how is it? Have you adapted to the Byakugan?" Mizuki asked, looking at him.

"Mizuki-jie, does the Byakugan consume a lot of chakra?" Riyue couldn't help but ask.

"Not at all, the chakra consumption is very low. A genin can keep it active for at least an hour, and a chunin can use it for four or five hours without any issues. A jonin can keep it active for even longer; sometimes when traveling and scouting, Hyuga jonin will keep the Byakugan active while on the move and only deactivate it when resting. Otherwise, wouldn't the Byakugan be useless in battle?" Mizuki said, looking puzzled.

"Then why does my Byakugan consume so much chakra? It was gone in just five minutes." Riyue felt deeply frustrated.

Mizuki activated her own Byakugan and said, "Are you channeling too much chakra? Activate it once and let me see."

Riyue waited until his chakra recovered to two-thirds and activated the Byakugan again. Mizuki watched his eyes intently, looking thoughtful. In less than three minutes, Riyue's chakra was exhausted again.

"Your chakra control is excellent, and the amount you're injecting is fine. It's just that the consumption is incredibly fast; it's basically drained the moment it enters your eyes," Mizuki said after a careful examination.

"Then what is going on?" Riyue felt miserable.

"I've never seen a situation like this, but I do know of something similar. The bloodline of the Hyuga main branch is much purer than that of the branch family; their Byakugan is known as the 'Pure Byakugan.' A long time ago, they were even called the Princess or Prince of the Byakugan. Their Byakugan abilities are stronger than the average branch family member, and their chakra consumption is lower than ours. But Riyue, your consumption is far too high; this is the first time I've seen such a case..." Mizuki mused.

The Princess of the Byakugan? I suppose that's what they were called back in the Otsutsuki era. I remember Toneri Otsutsuki calling Hinata that because of her pure Byakugan... Riyue pondered.

Could it be that my Byakugan is too impure? Does the bloodline influence it that much?

After resting for a while, Riyue activated the Byakugan again. He carefully observed the situation inside his body and saw that the chakra near his dantian was flowing rapidly through his meridians toward his eyes. The rate of consumption was astonishing; the Byakugan was like an insatiable monster, rapidly draining his chakra.

Riyue then looked closely at Mizuki, whose chakra flow for the Byakugan appeared much slower. He carefully compared the differences between them, then examined his Byakugan, meridians, tenketsu, lower abdomen, and chakra flow in detail, attempting to find the reason for the massive consumption. Finally, Riyue found a discrepancy.

"Huh? Why is it like this?!" Riyue was shocked to the core.