22 Shikai

Two years had passed, neither fleeting nor particularly long. The same river flowed by, a constant companion. Aizen sat on a nearby rock, silently focusing on refining his spiritual energy, known in his world as Chakra.

Compared to two years ago, Aizen's appearance hadn't changed much. His black hair, styled in the familiar three-point seven fashion (a Japanese hairstyle with bangs swept to the sides), framed a face that, while still handsome, had matured somewhat. He retained the black-rimmed glasses and the katana strapped to his waist, though he had grown taller, shedding some of his childish features.

With a final surge of concentration, Aizen completed his chakra refinement. The aura around him crackled with newfound intensity!"Finally, a mid-level Chūnin!" A satisfied smile spread across Aizen's face as he opened his eyes.

He stretched, a satisfied chuckle escaping his lips. A year ago, he had reached the peak Genin level in terms of chakra reserves. Today, he had finally crossed a major hurdle.While just a mid-level Chūnin, this level allowed him to lead a squad of ninja and enter the ranks of elite ninja. In his world, graduating ninja typically formed teams led by a Chūnin, with rare exceptions.

A metallic clang echoed as Aizen drew his katana. He vanished from the rock in a blur, his entire presence concealed. This technique, likely similar to Shunpo, allowed for near-instantaneous movement. A heartbeat later, Aizen materialized dozens of meters away within the forest. A flurry of blindingly fast strikes followed, each leaving a faint white streak in its path. Slowly, Aizen's figure emerged.

With a flourish, he sheathed his katana and walked out of the forest. Only then did the trees behind him begin to fall, one by one, like dominoes in a chain reaction." After my chakra level increased the power of my swordsmanship also increased." Aizen analyzed inwardly, feeling the fallen trees.

"Each strike held the power of high-level B-rank ninjutsu. The combined assault rivaled the force of an A-rank technique." Over the past two years, Aizen's swordsmanship had flourished. He had mastered the first level of a technique focused on body control, allowing him to concentrate a significant portion of his strength into a single point. At full power, his strikes could match the might of top B-rank ninjutsu. Coupled with his rudimentary high level Shunpo technique, honed over the past two years, the threat posed by a single strike was no less potent than an A-rank ninjutsu.

This deadliness extended far beyond what an elite Chūnin could manage, posing a serious threat even to some special Jōnin ."Unfortunately, the Chakra cost is immense," Aizen sighed. While the power boost to his swordsmanship was undeniable, the Chakra expenditure was a sobering reality.

Theoretically, Aizen could unleash ten strikes comparable to high B-rank ninjutsu, but that was his limit. Furthermore, ninja combat was a dynamic affair, not a one-trick pony. He couldn't rely solely on swordsmanship. More importantly, he needed to conserve at least one to two percent of his Chakra reserve after a battle for emergencies.

Being depleted of Chakra on the battlefield is a death sentence for any ninja! Aizen Sōsuke, a powerful captain from Soul Society with immense Reiryoku, might be an exception. However, the current Aizen is far from that level.

Over the past two years, Aizen diligently honed his Shunpo skills, enhancing his offensive and defensive capabilities. He also broadened his skillset by learning practical ninjutsu techniques, solidifying himself as a well-rounded ninja.

While Aizen trains rigorously, his physical prowess doesn't match that of expert swordsmen. He incorporates basic physical movement and combat techniques into his training. This focus on swordsmanship isn't due to a lack of interest in advanced physical skills. It's because his physical conditioning prioritizes the art of swordsmanship, a powerful martial art in itself, especially at a high level.

"The first stage of swordsmanship is complete. Now comes Zanjutsu," Aizen thought, his eyes gleaming with determination. "At this stage, swordsmanship delves into the realm of the soul, transcending mere physical exertion.

Traditionally, relying solely on physical skills and internal energy allows one to condense power up to a limit of ten percent. The key to breaking this limit lies in mastering Zanpakuto potential, which involves the soul.In layman's terms, it involves special soul techniques to refine and strengthen one's soul. This amplified soul power then integrates with the Zanpakuto, unleashing far greater power.

Currently, Aizen combines ten percent of his Reiryoku with his body to utilize B-level ninjutsu. However, once his sword soul is honed and reaches the state of Zanpakuto potential, he'll only need one percent of his energy for the same effect.Adding soul power isn't just about increasing sword's power.

Sword's core principle remains condensing one's entire body's strength. The soul's power acts as a conduit, channeling all the body's energy and Reiryoku into the blade, maximizing its potential.It's crucial that this channeling power is pure soul power. While Reiryoku has a spiritual component, it's not pure soul power.Essentially, cultivating the sword's soul is like cultivating another unique energy source.However, refining and cultivating the sword soul requires not only innate talent but also immense dedication and time. Soul cultivation is a delicate and complex process.

Orochimaru serves as a cautionary tale. His relentless pursuit of forbidden Soul Transfer Jutsu severely damaged his soul, rendering him vulnerable. Again, mastering sword requires patience and dedication.Aizen shook off his contemplation about sword power. He stopped by the river, recovering the Reiryoku he had just expended.

 After a while, fully recovered, Aizen focused his mind, and Kyōka Suigetsu, his Zanpakuto hidden within his soul, materialized in his right hand...He tossed Kyōka Suigetsu upwards and caught it in a reverse grip, the blade pointing downward perpendicular to his chest.

"Shatter the Heavens! Kyōka Suigetsu!"