The next day, Ling woke up early and went to the nearest training ground, as she had agreed with Shisui to learn genjutsu together yesterday.
Genjutsu is an extension of the Yin Release series, using various mediums to disrupt the enemy's Chakra, thereby interfering with their five senses.
Generally speaking, genjutsu needs to be cast using sound, light, or touch, so it's quite simple to shield oneself from it.
One only needs to prevent the enemy's light and sound from being perceived, or to distort the sound and light.
Might Guy once avoided falling for Itachi's genjutsu by not looking into his eyes, which is based on this principle.
Most of the Uchiha Clan's genjutsu are cast through the Sharingan, meaning through eye contact with the enemy, which ultimately relies on light transmission.
The Second Hokage, Tobirama, once created a genjutsu called Bringer of Darkness to counter the Uchiha Clan's genjutsu.
By depriving the enemy of light and creating an area of darkness, one would not fall for light-based genjutsu.
Sound-based genjutsu, however, is somewhat simpler; this type of genjutsu is only effective within a certain range, as the further the distance, the more distorted the sound transmission becomes.
Ling actually also has a technique that can ensure she doesn't fall for genjutsu, and that is the Wind Release Chakra Mode.
By forming a layer of wind curtain on the body's surface, the incoming light is distorted without affecting combat, which can block light-based genjutsu, while sound-based genjutsu can be rendered ineffective by the interference of wind sounds with the audio.
However, learning the incomplete Wind Release Chakra Mode and developing it to the extent of forming a wind curtain on the body's surface is still somewhat difficult.
Ling split into two Shadow Clones; one practiced the nature transformation of the Wind Release attribute, while the other studied Uchiha Ninjutsu.
She herself began to record a large number of genjutsu from the genjutsu scrolls, such as Haze Clone Technique, False Surroundings Technique, Demonic Illusion: Hellfire, Temple of Nirvana, and Sharingan Genjutsu.
The principles and analyses of various techniques greatly benefited Ling, giving her a certain understanding of the release, prevention, and dispelling of genjutsu.
These C-rank genjutsu are all very simple, but it is not easy to trap enemies with these simple genjutsu.
This is because the user needs to construct an extremely realistic genjutsu world; otherwise, the enemy can easily discover and break through it.
And to construct a realistic genjutsu world, one needs sufficiently strong spiritual power or Yin Release.
By pre-setting various genjutsu scenarios in your spiritual world, when you construct a genjutsu world in your spiritual world that approaches the realism of the outside world, you can be called a genjutsu master.
It is estimated that the peak Kurenai Yuhi could barely achieve this, while for the Uchiha Clan, constructing a genjutsu world is much simpler.
The Sharingan can assist in completing these steps, and the genjutsu analysis Ling obtained includes methods and techniques for constructing a genjutsu world.
Shisui didn't make Ling wait long before arriving at the training ground; his genjutsu strength was currently superior to Ling's, as he had studied this genjutsu analysis much earlier.
"Ling, it seems you've finished reading this genjutsu analysis. How is it? Do you feel confident in constructing a genjutsu world?"
Shisui was currently slowly learning to construct a genjutsu world, but his progress was slow because he hadn't yet awakened his Sharingan, and he was too young, with insufficient Chakra.
"I want to create a genjutsu myself, named Rabbit Body Replacement Technique or Escaping Rabbit Clone."
Ling recalled the Crow Body Replacement used by Itachi in the original work, which was a technique combining the principles of genjutsu, Body Replacement Technique, Summoning Technique, and Clone Technique.
Its insolubility was comparable to Orochimaru's Snake Body Replacement; although Ling didn't have crows as summoned beasts, she had a large number of Escaping Rabbits.
The Crow Body Replacement essentially shares Chakra with crows, allowing the crows to transform into one's appearance, and combined with the effect of genjutsu, it can achieve the effect that Itachi performs.
Shisui listened to Ling's explanation of the principle and felt that this technique indeed had great potential, and since he happened to raise a flock of crows, the Crow Body Replacement was also feasible.
So the two began to research this genjutsu in the training ground, and fortunately, both were geniuses, quickly deducing the technique.
Ling's enthusiasm surged; she switched her Heavenly Restriction to the Ten Shadows Technique, then summoned her Shikigami Escaping Rabbits and stored them in her shadow.
Shisui, meanwhile, was responsible for testing the technique's effectiveness; he would attack Ling as an enemy.
Facing the Shuriken thrown by Shisui, Ling smiled calmly.
"Rabbit Body Replacement Technique!" Ling formed a hand seal combining the Body Replacement Technique and Clone Technique.
Bang ~ A puff of white smoke flashed, and Ling's body instantly transformed into dozens of Escaping Rabbits, scattering in all directions.
Subsequently, several Escaping Rabbits were dispersed by Shisui; some of these Escaping Rabbits were real Escaping Rabbits, some were transformed by the Clone Technique and Transformation Technique, and some were illusions created by genjutsu.
Then, several Escaping Rabbits gathered together and reassembled into Ling's appearance.
Shisui was relentless, again using Body Flicker Technique to appear in front of Ling, drawing an arc with his Kunai and passing directly through Ling's body.
However, this body was merely one transformed from a Escaping Rabbit, further embellished with genjutsu.
This technique, combined with Shadow Clone, makes it somewhat impossible for even the Sharingan to see through, and those with lower genjutsu ability than Ling also cannot see through it.
In short, Ling played this technique with great flair, even more so than Itachi's original maneuvers.
After all, as long as the Escaping Rabbits are not all killed at once, they will continuously reappear.
These clones, transformed from Escaping Rabbits, have Chakra pathways due to the Chakra Ling distributed, making them completely unreadable.
With this technique, Ling's strength can be said to have greatly increased, at least to the point where even a Jonin would find her troublesome.
In one day, Ling and Shisui together created this troublesome Body Replacement Technique.
Moreover, Shisui's Crow Body Replacement could not compare to Ling's Rabbit Body Replacement Technique, as the number of crows is limited, and against extremely fast enemies, crows would quickly be injured or even killed.
Ling also didn't need to expend Chakra for summoning ninja beasts, allowing for longer sustainability.
"Ling, thank you for your idea and help. Let me treat you to ramen; a delicious Ichiraku Ramen shop recently opened."
Shisui was also very happy, firstly because he gained a very good technique, and secondly because researching techniques with Ling deepened their bond.
If Ling knew Shisui's thoughts, she would probably feel a chill down her spine, thinking, 'Could this kid be planning to make me a sacrifice to awaken his Mangekyo?'
"Alright, I'm hungry anyway." Due to her Heavenly Restriction, Ling had become a big eater.
Her stomach constantly rumbled with hunger, forcing Ling to always carry various high-calorie snacks with her.
The opening of Ichiraku Ramen made Ling feel a sense of disconnect, like an anime turning into reality; Teuchi Ichiraku was still a young man at this time.
The shop's business was good, so the taste must be decent, but Ling was carefully observing Ichiraku's aura.
She finally determined that Ichiraku was not an Ōtsutsuki Clan, as he had no Chakra, and sensing him in terms of Curse Power only revealed a weak soul.
The new shop's opening offered cheap prices, large portions, and decent taste, though the variety of ramen was still very limited, indicating it wasn't the peak Ichiraku yet.