If you ask Shisui what the difference is between training in a Full Concentration Breathing state and normal breathing, it's like how normal breathing is like taking bites during a meal to gain sustained power, while Full Concentration Breathing is like suddenly taking a big bite to gain a burst of power.
The difference is that practicing Full Concentration Breathing is much harder than just taking a big bite of food, which only requires opening your mouth wide and controlling the muscles in your mouth. Full Concentration Breathing isn't about just opening your mouth wide and taking a deep breath.
The training for Full Concentration Breathing is somewhat akin to sprint training, enhancing one's explosive power bit by bit.
On Friday, when Shisui first learned it, he didn't feel much different than usual. He tried hard to concentrate his breathing but didn't notice any significant change.
This situation didn't change until the fifth day.
"Breath of Flame, Full Concentration Breathing, Impatiens Claw Red!"
Shisui held four kunai between the fingers of his right hand, concentrating Chakra in his palm. In just an instant, all four kunai were engulfed in flames, and then he quickly launched them.
Boom Boom!!
The kunai, wrapped in fiercely burning flames, were like small fireballs. Upon hitting the ground, they exploded and blasted out small craters.
"No-seal release? Shisui, how did you do that?" Obito couldn't resist asking curiously.
Obito had once gathered flames in his hand during a practical exam to attack Might Guy. If speaking only in terms of Ninjutsu, that could barely be considered a No-seal Jutsu, as it also involved Chakra Nature Transformation.
But in reality, what Obito did was just a normal Nature Transformation technique, where the flames were just ordinary flames, without any added effects. He also couldn't increase their power by adding more Chakra, as it would easily burn him.
If rated by the learning standards of the Ninja World, Obito's technique would at most be D-rank, not in the same league as Shisui's No-seal Impatiens Claw Red just performed.
"It's not a true No-seal release; I just took advantage of Full Concentration Breathing," Shisui explained.
"Generally speaking, gathering Chakra in the throat to release Fire Release is safer and easier to condense. The hand is more dangerous and slower..."
In the human body of the Ninja World, there's a Chakra Meridians system and 361 Chakra Acupoints throughout. However, the difficulty of gathering Chakra and performing Nature Transformation varies by body part.
That's why so many Fire Releases are expelled from the mouth, as using hands and feet is inefficient and can easily harm oneself.
Different Nature Transformations also differ. For instance, Lightning Release and Fire Release are different; many Lightning Releases concentrate Chakra in the hands or arms to release.
"The Breath of Flame can solve the problem of Nature Transformation speed. Also, reducing the number of shuriken lowers the total flame requirement. Lastly, I did form a seal," Shisui showed his left hand to Obito, having just formed a single-hand seal.
The essence of forming seals is to guide Ninjutsu. He weakened and enhanced with the Breath of Flame, barely managing to perform a Single-Handed Seal release of Impatiens Claw Red.
"Seals can be done with one hand?" Obito was shocked.
Smack!
Mokgetsu pressed two fingers together and gave Obito a jab.
"Looks like you forgot what I taught before," Mokgetsu said while ruffling Obito's hair.
"The essence of forming seals is to guide the release of Ninjutsu. If you understand Ninjutsu well enough, you can form seals with one hand and even reduce or eliminate seals," Mokgetsu reminded him.
Mokgetsu's words jogged Obito's memory.
It seemed Mokgetsu had talked about one-handed seals and simplifying seals before, even demonstrating Mighty Dragon Fire with a full seal and a single seal.
After listening to it that day, Obito excitedly tried it out, only to find that not only was one-handed sealing not faster, but it also resulted in a failed Ninjutsu release.
After several days of no progress, Obito stopped trying, thinking regular training was better, as he hadn't heard of any powerful ninja becoming famous through one-handed sealing.
"Hehe, I just wanted to test if Shisui remembered what Teacher Mokgetsu taught," Obito said, putting on an act.
Shisui: ...
"The idea is quite good. Although the power and attack range are smaller than a normal Impatiens Claw Red, the release speed is faster, which might work unexpectedly at close range," Mokgetsu said.
If someone believed Shisui couldn't release Ninjutsu in time and charged at him with a sword, a sudden single-hand seal Fire Release from Shisui would likely be difficult to dodge.
"Teacher Mokgetsu, could you explain Single-Handed Seals again?" Obito looked at Mokgetsu with anticipation, wanting to perform a stunning single-hand seal release of Impatiens Claw Red like Shisui.
Obito imagined it would look really cool in a real battle.
In combat, he would nonchalantly pull out four kunai, and before the enemy knew it, instantly form a single-hand seal and launch four flaming kunai, piercing the enemy with fiery kunai, leaving them blown to bits. And after throwing the kunai, he'd coolly put his hands in his pockets and turn away.
"Seeing such a cool scene, Rin would definitely look at me with admiration and say, Obito, you're amazing," Obito fantasized.
"I've actually already explained everything before. Today, I'll explain it again. It really requires you to familiarize yourself with Ninjutsu more through practice; just listening is hard to learn from," Mokgetsu said.
Explaining single-handed sealering, it's like asking a right-handed person to practice calligraphy with their left hand, or write calligraphy with both hands. The teacher can't practically possess you to teach.
However, single-handed sealing does have significant practical value in real battles. If wearing a long robe, you could completely hide the hand forming seals and secretly unleash Ninjutsu.
It sounds a bit sneaky, but it's extremely practical in battle. If the enemy can't see your seals, even if they sense you might use ninjutsu, they won't know which jutsu it is.
Experienced warriors can tell the type of ninjutsu just by observing the seals, as different elemental jutsu have corresponding characteristics. For example, Fire Release typically ends with a Tiger Seal.
"Mm-hmm, I'll practice more." Obito nodded rapidly like a pecking chicken.
"Shisui, can you share some of your success experiences with me?" Obito then looked toward Shisui.
"No success experience because I forgot what Teacher Mokgetsu taught." Shisui replied.
"Huh?" Obito showed a surprised expression, then recalled what he had just said.
"Haha, I forgot, how could Shisui forget? Didn't you just perform it?" Obito quickly admitted his mistake and said.
Shisui was just joking. With such an expectant look from his companion, he naturally wouldn't refuse.
"To make a breakthrough with seals, ninjutsu practice is indispensable. Additionally, your current level requires the assistance of the Breathing Technique, try practicing both simultaneously." Mokgetsu began the instruction.
Then Obito began his journey of single-handed seals.
The first try was somewhat awkward. Obito completed the seal with one hand, but the shuriken was thrown, and no fire was released.
Obito and Shisui asked about advanced experiences.
Looking at the shuriken scattered on the ground, Shisui appeared somewhat silent. He encountered a knowledge gap; he hadn't faced this situation before.
At this moment, he was wondering why someone would throw the Impatiens Claw Red Shuriken, and no fire was released. Usually, fire is sprayed first, then the shuriken is thrown.
After thinking for a long time, Shisui couldn't figure out how to make a mistake at this step, so he said:
"How about you practice double-handed seals first to get familiar before doing single-handed?"
"Good idea!" Obito thought it was a good approach.
Double-handed seals naturally completed the ninjutsu smoothly, with dozens of flaming shurikens crashing onto the ground.
Obito recalled the memory of the double-handed seals and attempted to complete the seal with one hand.
The second time he performed single-handed seals for the ninjutsu. This time, fire was released from his hand, nearly burning Obito himself.
"Haha, I kept thinking of Shisui using hands and forgot the steps." Obito explained with a laugh.
Shisui seemed to have discovered the reason why Obito couldn't perform single-handed seals.
"Single-handed seals are more difficult than double-handed ones, requiring more concentration, and don't let your mind wander." Mokgetsu reminded.
Completing with one hand what is usually done with both naturally adds difficulty.
Two hours later, Obito became more proficient in channeling chakra into his palm, but the single-handed seal was temporarily unsuccessful.
After training ended, everyone went home, but actually, Shisui was the only one who went home. The others regrouped in the Southern Border Forest after going home.
At the entrance, changing shoes and entering the house, Shisui poured himself a glass of water.
He didn't have the habit of saying "I'm home" because no one would respond; he lived alone.
Looking at the calendar on the wall, Shisui realized it was already October 18th.
His birthday was on October 19th, just tomorrow.
However, Shisui didn't plan to celebrate. The only one who knew his birthday was his uncle, who had recently gone on a mission and wouldn't have time to celebrate with him.
He didn't want to proactively tell Mokgetsu and the others about his birthday. He believed Mokgetsu would help him celebrate once he knew, but Shisui didn't want to trouble Mokgetsu for such a trivial matter.
Mokgetsu was already very busy, teaching the first class year-round at the Ninja Academy, squeezing in extra time to teach them morning and noon, and heading to the Southern Border Forest right after school, recently injuring himself while forging ninja tools.
Seeing Mokgetsu so busy, how could Shisui trouble him with such a small thing as a birthday? Celebrating a birthday wouldn't increase his strength, offering no benefits to him or Mokgetsu.
"It's just a sign of getting a year older." Shisui sat in the courtyard, looking at the bright moon in the sky.
After some scattered thoughts, Shisui ultimately chose to practice ninjutsu.
Perhaps due to a chaotic mind, this time, when Shisui threw four shurikens, two of them didn't have flames attached.
"So that's how it is…" Shisui somewhat understood the reason for Obito's failure to release the technique earlier in the day.
On the other side, Mokgetsu gathered the disciples, excluding Shisui.
"Do you know what day tomorrow is?" Mokgetsu asked.