Before long, Yashui woke up. The Three-Legged Golden Crow would never be too hard on its own student.
"How do you feel, Yashui?" the Three-Legged Golden Crow asked nonchalantly.
"It feels... pretty terrifying... That genjutsu was so realistic." Yashui answered, still dazed.
"I'm asking how your body feels," the Three-Legged Golden Crow asked again.
"My body..." Yashui looked at himself, then at the Three-Legged Golden Crow. He couldn't see any chakra pathways. "I guess the Sharingan is shut off."
"That was only a temporary fix. To solve the problem for good, Sealing Jutsu may be the only way." The Three-Legged Golden Crow looked troubled, too. "That's enough for today. Practice at home by yourself tomorrow, and don't come back. Come again in twenty days."
"Master, don't you know Sealing Jutsu?" Yashui asked anxiously. "If you can fix my eyes for good, please don't hold anything back."
"My Sealing Jutsu wouldn't work on you." The Three-Legged Golden Crow glanced at Yashui. "There's no point worrying. I'll ask around elsewhere about Sealing Jutsu over the next few days."
"Th-thank you, Master." Yashui had misjudged the Three-Legged Golden Crow earlier. He'd thought his master was holding back by refusing to use Sealing Jutsu to help him.
"Yashui." The Three-Legged Golden Crow called out to him before he left. "I left a genjutsu trap in your mind. If your Sharingan opens again, it'll activate automatically and use genjutsu to deactivate it. But it'll only work once."
"I'll be careful." Yashui bowed gratefully to the Three-Legged Golden Crow, then released the Summoning Technique.
Yashui returned to his house. He took off his sunglasses and gazed into the mirror at the eyes that didn't belong to him, his mind filled with complicated emotions.
For now, he'd better finish the task the Three-Legged Golden Crow had assigned him.
Yashui bought another two jin of rice wine. For the next several days, he stayed cooped up inside his house with the doors locked and the curtains drawn. He refused to come out, no matter what.
Everyone in the Sarutobi Clan was concerned about Yashui, afraid he might have developed some kind of mental illness.
Whenever they asked, Yashui fobbed them off with some excuse. He was grateful for their concern, but it wouldn't make him stronger. He needed to train quietly by himself if he wanted to grow stronger.
Twenty days flew by. During that time, Yashui had spoken to no one except the Third Hokage, Konohamaru, and Sarutobi Asuma. He'd nearly lost the ability to speak.
He'd already spent far longer on this training than the fastest student the Three-Legged Golden Crow had ever taught.
Yashui could only sigh. He really wasn't a genius.
Even if he wasn't a genius, Yashui was working hard enough. Lately, apart from completing the Three-Legged Golden Crow's goal, he hadn't thought about anything else.
As he kept thinking it over, Yashui also realized the true purpose of this training.
Yashui had assumed the training was meant to improve his chakra extraction speed, and the Three-Legged Golden Crow hadn't denied it. But that wasn't its only purpose.
As he trained, Yashui's chakra extraction speed kept increasing. By the tenth day, it had caught up with his chakra output speed.
It turned out that increasing chakra extraction speed wasn't very difficult. Once you got the hang of it, you just had to push a little harder, and anyone could quickly improve their chakra extraction speed. The Konoha jōnin could extract chakra much faster than Yashui could now when they performed advanced ninjutsu.
Yashui also realized how important chakra extraction speed was in battle. For example, if a particular jutsu required 100 units of chakra, and a ninja could extract 50 units per second, they would need two seconds to gather the chakra for the jutsu while completing the Hand Seals.
If the ninja could only extract 40 units per second, it would take 2.5 seconds. That extra half second would give the enemy a huge opening.
If a ninja who could extract 40 units per second tried to cast the jutsu in two seconds to save time, they would only have 80 units of chakra for a jutsu that required 100. The jutsu would be weaker, and it might even fail.
That was why chakra extraction speed mattered. Of course, it had to keep up with output speed. Extracting a lot of chakra without putting it into a jutsu was no different from not extracting any at all.
Only when both chakra extraction and output speeds were fast enough was it worthwhile to practice Hand Seal speed. Otherwise, you might finish the seals before your chakra was ready, which would be awkward.
But simply increasing his extraction speed didn't seem to make the rice wine boil. During training, Yashui often ran into the same problem: at the start, both his chakra extraction and output speeds were fast.
But halfway through, the chakra in his cells couldn't keep up. At that point, extracting chakra felt like squeezing toothpaste from a tube. He had to wring it out of his body bit by bit. His extraction speed dropped sharply, and his output slowed along with it.
That happened because the cells that had just been used to extract chakra became fatigued.
Yashui realized there were two ways to solve the problem. The first was to increase the total amount of chakra stored in his cells and improve their stamina. That would take long-term training. He had spent this whole period wringing chakra out of his cells, so his chakra reserves had increased a little, but nowhere near enough.
The Three-Legged Golden Crow had said the fastest student could finish this task in just fifteen days. It was impossible to greatly increase one's chakra reserves in fifteen days, so Yashui figured the first method couldn't be the answer.
The second method was to shift the focus of his chakra extraction quickly to areas he hadn't used yet, once he'd finished extracting chakra from one area.
Yashui spent five days refining the second method, then another five practicing it. Only then did he master it.
When Yashui completed the training, he first extracted chakra from the left half of his body. Once the extraction speed there began to slow, he switched to the right half, letting the left side rest.
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