The First Hokage looked at Aki with a serious expression. "There are three basic ninjutsu that are foundational to every shinobi," he explained. "The Transformation Technique, which allows you to change your appearance into objects or other people; the Clone Technique, which creates non-physical afterimages to confuse the enemy; and the Substitution Technique, which allows you to instantly swap places with an object to evade an attack. Today, I will teach you an advanced version of the Clone Technique that I developed."
Hashirama crossed his index and middle fingers into a cross shape. "Shadow Clone Technique!"
With a burst of smoke, an identical copy of the Hokage appeared beside him. "This creates a physical entity by splitting your chakra in half," they explained in unison. "The clones share your abilities but vanish after one hit. However, their true value lies in their experience; when a clone is destroyed, everything it learned—whether training in ninjutsu or taijutsu—is transferred instantly to the original's mind. This can drastically reduce training time, but it carries the risk of mental overload. If used improperly, it can leave a person brain-dead."
Hashirama dispelled the clone and produced a scroll. "During my years as Hokage, I interacted with many nearly extinct professions, including Samurai and Onmyoji," he said. "Many modern sealing techniques are actually modified versions of ancient Onmyoji arts. From them, I obtained a manual focused on cultivating mental energy. Mastering this Yin-Yang Mantra will allow your mind to withstand the feedback of the Shadow Clones."
Aki looked at the manual. "Have you practiced this yourself, Master?"
"No, I never had the time," Hashirama laughed. "But mental energy is essentially self-control and the willpower you use to dominate chakra. This mantra will enhance that. Don't worry, I will only step in if it looks like you're about to lose your mind." Aki remained silent, inwardly feeling like a human guinea pig for the Hokage's experimental training.
The Hokage's Office
"Lord Second," an Anbu operative reported, kneeling before Tobirama Senju. "Our spies in the Hidden Stone report a massive mobilization of shinobi toward the border of the Hidden Waterfall. It appears they are preparing for a major operation."
Tobirama stared out the window at the village. "Is war truly coming again?" he sighed. "Alert our operatives to confirm the Hidden Stone's exact movements immediately."
The Land of Lightning: Raikage's Office
"Are you certain they are heading for the Land of Lightning?" the Second Raikage asked, looking at his intelligence report. His spies confirmed that nearly two thousand shinobi led by Onoki, the disciple of the Second Tsuchikage, had entered the Hidden Waterfall.
Kin-gaku (Kinkaku), a muscular man with horns and a "Gold" character tattooed on his shoulder, slammed his fist on the desk. "We should strike first! Destroy the Waterfall and conquer the surrounding small nations to catch up to the Leaf's strength!" His brother, Gin-gaku (Ginkaku), agreed. "The First Hokage is rumored to be failing after his fight with Madara. This is the perfect time to test Konoha's limits."
The Raikage looked at the brothers, who had famously survived being swallowed by the Nine-Tails. "You think you are invincible because you have a bit of the Nine-Tails' chakra?" he countered coldly. "Hashirama and Madara could kill you both easily. Our goal is to monitor the Stone and consolidate our forces. Dismissed."
As they left, a white-haired shinobi asked the Raikage why he didn't purge the troublesome brothers. "They are high-level assets," the Raikage replied. "When the war starts, I will put them on the front lines. Let's see if they survive."
Six Months Later: The Forest of Death
"Wind Style: Great Breakthrough!"
Aki appeared behind Hashirama, unleashing a gale of wind. The Hokage spun around, weaving signs. "Wood Style: Wood Locking Wall!" Wooden pillars erupted from the ground, forming a protective arch that absorbed the wind.
Aki didn't stop. He slid to the right and wove more signs. "Fire Style: Hiding in Dust and Ashes!" (Katon: Zukokku). Clumps of fire erupted from his mouth, exploding around Hashirama and creating a thick screen of smoke.
As the smoke cleared, Aki appeared behind Hashirama's neck with a long blade. "You were distracted, Master. I win."
Hashirama nodded approvingly. "Using the Sharingan to track chakra, the fire to obscure vision, and a Body Flicker for a lethal strike... a very clever combination. But it only works on Genin." The Hashirama before Aki suddenly vanished in a cloud of smoke.
"A Shadow Clone! No!"
"Wood Style: Forest of All Creation!"
Roots erupted from the earth, binding Aki before he could react. Hashirama appeared before him. "The Sharingan can see chakra, but there are many ways to deceive it—my Shadow Clones are one," he said. "Your chakra levels are now at the level of a Chunin, but your combat instincts are still lagging behind a Genin. Training here is finished. It's time to go home."
Aki bowed deeply. "Thank you for these six months, Master. I will never forget how you used your own energy to temper my body."
"Protecting Konoha with your life is the only repayment I need," Hashirama replied firmly. Together, they left the dark tower and headed back toward the lights of the village.