Tenkaichi| Kojiro Sasaki

The 16 warriors are:Honda Tadakatsu Miyamoto Musashi Sasaki Kojiro Hattori Hanzō Yagyū Munenori William Adams Fūma Kotarō Kamiizumi Ise-no-Kami Nobutsuna Hino Chōkō All Seigen Akechi Mitsuhide Nagamasa Azai Niohmaru Itō Ittōsai Yagyū Jubei Ogasawara Nagaharu

Tenkaichi: The Greatest Warrior Under the Rising Sun is an action manga set in an alternate history world.

The story takes place in a Japan where Oda Nobunaga never died and succeeded in unifying the country. Ten years later, in 1600, he discovers he has a terminal illness. Instead of naming an heir, he decides to organize the Tenkaichi Tournament.

The rules are simple: 16 daimyo (feudal lords) each choose their strongest warrior. The 16 warriors fight in a single-elimination tournament. There are no rules against killing opponents. The daimyo whose champion wins the tournament will become the new ruler of Japan.

Kojiro is a burly man who wears a haori with a patterned hem over a traditional kimono; he carries a large Japanese sword strapped to his back and another at his left hip. His dark hair is tied back in a long ponytail that falls down his back, framing his face with two large, emo-style bangs. Although Kojiro usually wears a Noh mask of an old man, beneath his appearance lies an androgynous beauty, to the point that even Ranmaru couldn't tell if he was a man or a woman.

Sasaki Kojiro appears to be a very peculiar yet perceptive individual, possessing a sharp, almost mechanical, perception. He approaches combat with an analytical mind, dissecting his opponent's movements with precision, as seen during his battle with Hanzo. Here, Kojiro meticulously breaks down every element of Hanzo's stance, gaze, and balance, calculating his next move with the cold efficiency of a machine, while showing little understanding of Hanzo's more emotional reasons for fighting (at one point, he asks if there's literally a dead man helping him when he claims to be fighting for Tadakatsu).

Despite his impassive appearance, Kojiro has displayed irrational behavior in his obsession with Musashi and his swordsmanship, seemingly due to his resemblance to Kuro. He appears almost infatuated with the swordsman, wanting him to witness his skill at all costs and interrupting the battle to stare intently at him during combat, much to Musashi's discomfort and annoyance.

During the battle against Hanzo, the ninja finally manages to break through Kojiro's cold shell through sheer willpower, causing Kojiro to finally express his emotions and show genuine anger and frustration at Hanzo's apparent immortality.

More than ten years earlier, amidst the wreckage of a battlefield likely lost to history, Kanemaki Jisai found Sasaki Kojiro laughing before his father's corpse. As he approached the boy, Sasaki turned his attention to Kanemaki, pointing his katana at him. Surprised by the boy's reaction, Kanemaki asked him why he was laughing on a battlefield. Sasaki replied that his father had told him not to kill without reason, because that's what strange people do. In a war that seemed pointless, finding his father dead struck him as odd, and strange things, to him, were funny. This peculiar behavior amused Kanemaki, who offered to train Kojiro, initially offering Sasaki strength; however, the boy only accepted because his mother had advised him to stay safe.

To surpass Ito Ittosai, Kanemaki Jisai gathered thirty children, orphaned by the chaos of war and the infighting among those most inclined towards martial arts. Kanemaki set his plan in motion. To strip them of their individuality, he forced them to wear identical Noh masks and gave them numbered names, thus erasing their wills and personal identities. Under the guise of hunting demons, Kanemaki trained them mercilessly, aiming to forge warriors fearless in the face of death.

As part of their brutal training, Kanemaki selected bandits, mountain robbers, and ruthless ronin for his students to practice on, turning them into precision killing machines. Among the thirty, two stood out: Kuro and Jiro (Sasaki Kojiro).

During one of these training sessions, Kuro pushed Sasaki with one hand, sending him sprawling to the ground. When some students approached Kuro, implying that she had touched Sasaki's chest on purpose and questioning her gender, Kuro angrily dismissed them. She then approached Sasaki, asking if she was alright, and Sasaki, oblivious to the others' insinuations, assured her that she was fine.

While many of the other children were drawn to Sasaki, perceiving him as a "pretty girl," he remained aloof, focused solely on his training. Later, Kuro took Sasaki to a secluded cliff in the mountains, seeking a private conversation. Kuro told Sasaki that he was disturbed by the way the other children viewed him and that their intentions toward him reminded him of those "demons" they used to kill. Kuro also expressed to Sasaki the protective instinct he felt for him, warning him that he could become a "demon." He told him they had to leave that place and that, once outside, Sasaki's closed heart would open. Kanemaki, who overheard everything, considered Sasaki a poison to Kuro and stated that he must eliminate him, along with Kuro's heart, to create his ultimate masterpiece. With this goal in mind, Kanemaki subjected them to a test: "The Poison Pit."

During a test imposed by Kanemaki, Kojiro and other students were sent to eliminate a clan in a mountain village. Kanemaki deliberately manipulated the students with lies and promises of pairing them with Kojiro, turning them against each other and transforming the test into a fight for survival. Blindly following the orders he had been taught, Kojiro came to see Kuro as a "demon" and fought him, ignoring his attempts to reason with him. At that moment, the desire his mother had instilled in him to "stay alive" clashed with the absolute obedience Kanemaki had instilled in him. During that confrontation, he awakened the Map of Creation. After the test, Kanemaki ceased to see him as a person and began to use him solely as a weapon of war.