Chapter 10: Total Aura Capacity
Barring any surprises, Haru planned to focus his training on Manipulation, with Emission as a secondary priority.
As for Specialization, unless some extraordinary event occurred, it seemed beyond his reach.
The energy and effort saved from not pursuing Specialization could instead be allocated toward training in Enhancement.
Though his efficiency in training Enhancement was only 60%, and it required far more effort compared to a natural Enhancement user, it was still better than leaving the potential untapped.
Thus, Haru continued his solo training. He alternated between Ten, enveloping his body in aura, and Zetsu, closing his aura nodes entirely. These drills improved his proficiency and felt relatively simple to grasp. Along the way, he also practiced Gyo.
While Gyo isn't one of the four core techniques, Haru considered it another way to manipulate aura, bridging Ten and Zetsu. It involves concentrating aura into a specific body part, such as the eyes, to enhance perception.
Haru quickly found Gyo easier than expected. Within a minute, he could activate it at will, enhancing his vision. Looking down, he saw a faint layer of white aura enveloping his body. Gazing into the forest, his eyesight sharpened, allowing him to distinguish the texture of Toru's fur even from a distance.
After about half an hour, Haru decided to move on to Ren, also referred to as Ken when sustained.
Taking a deep breath, he opened all his aura nodes and released his energy at maximum output. This surge of aura is Ren. Sustaining this state is known as Ken.
Gritting his teeth, Haru held the state as long as he could.
The terminology might seem overwhelming, but the concepts were straightforward. It all boiled down to variations of aura manipulation.
Ordinary people are fragile. Even trained fighters pale in comparison to Nen users, who can exponentially enhance their physical offense and defense with basic aura control. This capability bridges the gap between mortals and superhumans.
Ten allows for consistent, moderate aura protection, akin to jogging—manageable over extended periods, even 24/7 with practice. Ken, on the other hand, maximizes defensive strength but is akin to an all-out sprint—powerful but unsustainable for long.
According to Biscuit Krueger, a veteran Nen master, sustaining Ken for at least 30 minutes is the baseline for survival in serious battles.
Without this endurance, Haru's Song of the Earth—his manipulation ability—would be easily countered. If an opponent used Ken to block his Star Mark and retaliated with a devastating strike, his ability's potential would be wasted.
Foundational strength, therefore, was paramount.
Nen's aura capacity could also be quantified.
A Nen specialist in the Hunter Association estimated that sustaining Ken consumes approximately 1 aura unit per second. By measuring how long one can sustain Ken, a Nen user can gauge their total aura reserves and work to increase them over time.
For example, in the manga, after training on Greed Island, Gon and Killua's total aura capacity ranged from 3,000 to 3,300 units, as Killua could sustain Ken for 55 minutes. Post-training, Gon's capacity increased to 21,500 units, allowing him to sustain Ken for nearly six hours before exhaustion.
Biscuit's benchmark of 30 minutes translates to around 1,800 units of aura—a minimum threshold for survival. Falling below this level leaves one vulnerable to attrition from stronger opponents.
"Damn…" Haru muttered as he practiced Ken.
Counting silently, he reached 60 seconds before his aura began flickering like a dying lightbulb.
At 70 seconds, sweat poured down his face, and the aura radius shrank.
By 80 seconds, his entire body ached, and the aura clung tightly to his skin as if resisting collapse.
"Ninety-seven… ninety-eight… ninety-nine…"
With a final gasp, his aura sputtered out entirely, like a flame consuming its last drop of fuel.
"One hundred!" Haru collapsed onto the ground, drenched in sweat and utterly spent.
"...So my total aura capacity is only 100 units," he murmured, staring at the sky through the forest canopy.
Reflecting on some rough calculations, Haru recalled that when Gon reached 21,500 units, he could output 1,800 units in Ken, approximately one-twelfth of his total capacity. This ratio seemed to be a universal limit dictated by human physiology, much like how no one can sprint at full speed until complete exhaustion.
By this logic, Haru's Ken output likely hovered around 8–9 units. Given that he was a Manipulation user, whose Ken strength was capped at 60% efficiency in the Enhancement domain, his effective defense was probably only 4.8–5.4 units.
The realization was sobering.
"...I'm so weak."
Lying on the ground, Haru groaned in self-deprecation as Toru's face suddenly appeared in his field of vision.
"What? You think I'm dead?" Haru chuckled, patting the tiger's head. "I'm just taking a break."
After ten minutes of playful wrestling with Toru, Haru finally got back on his feet.
"With Star Mark helping my recovery, I only need ten minutes to bounce back. Without it, who knows how long I'd need after just two minutes of Ren…" He sighed. "Man, it'd be nice to have Biscuit's Cookie Assistant—that Nen ability is a training godsend."
Star Mark could heal injuries and provide some stamina recovery, but Biscuit's massage-based ability specialized in restoring energy and dispelling fatigue.
"Anyway," Haru resolved, "let's set a small goal: raise my total aura capacity to 1,000 units first!"
Taking another deep breath, he unleashed his aura and began training again.
---
Meanwhile, in the Kakin Kingdom's royal palace, First Prince Benjamin Hui Guo Rou studied a newly appeared five-pointed star on his palm.
This marked the death of his operative, Musser, the night before.
After a long silence, Benjamin picked up the phone. "Summon Babimyna."
(End of Chapter)