Senju Clan Ancestral Relic

The stone door did not open. But beside the sunken footprint on the stone steps was another crack.

Shinichi only discovered this during his second visit to the Senju Ruins. Last time, it had been too dark, and the glowing moss in the forest had been mostly covered by vines. He had focused entirely on sensing the sealing formula inside the stone door and completely failed to notice the narrow fissure beneath the wall to the right of the steps, nearly blended into the rock's natural grain. The crack formed an irregular quadrilateral, its edges bearing obvious chisel marks from tools. It was so old that the marks had nearly been worn away by the elements. If he had not crouched down to tie his shoelaces and happened to look at that exact height, the crack would probably have remained forever in his blind spot.

He ran his finger around the crack and felt a faint current of air against his fingertips, indicating that it was hollow inside. The gap was too narrow for a hand to fit through. But a snake could. He pulled out a spare thin iron wire from the ninja tool pouch on his leg, bent it into a hook, and carefully probed along the marble edge. When it caught against something metallic, there was an extremely slight rebound. He gently nudged it toward the opening, then hooked its narrow edge with the wire and slowly dragged it out. It was a thin copper plate, smaller than his palm. Its surface was long covered in verdigris, but after he brushed away the dirt, he could vaguely make out traces of the rustproof glaze it had once been coated with. The front of the plate bore a shallow-relief diamond pattern, perfectly matching the outline of the Senju Clan crest on the back of Shinichi's school uniform.

As expected, it belonged to the Senju Clan.

The copper plate was only a marker. The true relic lay in a deeper hidden compartment. He thrust his entire arm into the crack, and his fingers touched a cloth bundle. The moment he touched it, he knew the material was no ordinary fabric—rough, yet resilient. Though it had been buried underground in dampness for decades, it had not rotted at all, and faint chakra fluctuations still lingered between its fibers. As he pulled it out, his fingers were lightly bounced away, and an exceedingly weak repulsive force passed across the cloth's surface. Some kind of protective sealing formula had decayed to the very edge of failure, leaving only one thin final barrier.

Inside the bundle was a notebook. Its cover was dark brown leather, its corners worn pale. The binding had been restitched many times, old and new threads overlapping like a dense spiderweb. There was no title on the cover, only four words written in charcoal pencil in the lower-right corner. The handwriting was sloppy, but the strokes were vigorous and forceful.

"Senju Legacy."

Shinichi turned to the first page. The paper was thin enough to let light through, and he had to be exceptionally careful with every turn, or the edges would crumble into powder. The handwriting inside was identical to the four charcoal-written words on the cover. The format was as simple as an experimental log—date, training content, test results, remarks. The first half contained nothing but combat summaries and meditation insights. Some pages still bore old stains that might have been tea or medicinal juice, and occasional complaints were tucked among the writing, making it unexpectedly vivid. But what truly made him hold his breath was the latter half of the notebook. At the top of one page, bold characters read "Sage Body: Advanced Record," and below it, seven stages of the Sage Body, from awakening to maturity, were listed one by one in vertical format.

Stage One: Bloodline Awakening. The Senju bloodline is initially activated, chakra reserves surge, the body develops plant-like traits, and regenerative ability begins to emerge. Stage Two: Sage Foundation Body Forging. Through external stimulation—sage chakra, natural energy, or resonance with the bloodline of a close relative—the chakra pathways are broadened, a reservoir of vitality takes shape, and regeneration speed rises dramatically. Stage Three: Source of Life. One can actively infuse one's own vitality into another person's body, instantly healing external wounds. This stage requires a large amount of natural energy as a catalyst. Stage Four: All Things in Nature. Wood Release and the Sage Body fully merge. The body can naturally absorb faint chakra from the environment to replenish its expenditure, granting nearly limitless endurance. Stage Five: Indestructible Body. All cells throughout the body enter a state of hyper-regeneration. Severe injuries such as reattaching severed limbs and repairing organs can be completed in an extremely short time, while the rate of aging slows dramatically. Stage Six: Life Resonance. One can establish chakra resonance with the earth, plants, summoned beasts, and even other people, using oneself as the hub to construct a life network covering an entire battlefield. Stage Seven: Source of Life: Ultimate. One's vitality is transformed into a "seed flame," allowing one to remain in the world in chakra form after the physical body perishes, or to be reborn within a new host.

The handwriting had visibly slowed by the end of the seventh stage, the ink growing intermittent. The final sentence only filled half a line—"This stage is merely a theoretical deduction. Even the ancestors were unable to verify it in person. If one could reach this point, one would no longer belong to the realm of ordinary men."

Then the brushwork changed abruptly. It was clearly a different writer. The handwriting lacked the earlier strength and vigor, instead carrying the sharpness of youth, with short unfinished flicks at the end of strokes. The person who had taken up the pen added a small line beneath the seventh stage: "If one can truly reach the Source of Life: Ultimate, even a mortal may stand alongside the Six Paths. —Hashirama."

Shinichi's fingers stopped over the page when he saw the two words "—Hashirama."

This notebook had not been written by some elder from a Senju branch family—the first half was Hashirama Senju's own training log, while the later addition was Tobirama Senju's. Konoha's First and Second Hokage had each left their mark in this book. What he held in his hands was not a mere cultivation journal, but the Sage Body evolution roadmap personally written by the First Hokage, valuable enough to be stored in the deepest vault of Konoha's archives.

He gently closed the notebook to calm himself for a moment, then opened it again.

In the latter half, Hashirama had added a page written specifically for himself. The tone was much more casual, as though he had scribbled it down while sitting on the ground after training.

"I didn't write this stuff so future generations would worship me. I wrote it because I suffered too much while training it myself. The fewer people walk the Sage Body path, the more important it is for someone to record all the pitfalls. If some brat finds this notebook in the future, remember this: don't rush from the first stage to the second. Soak in hot springs a few more times first. Train only after your chakra pathways have loosened up. I was too impatient back then, and the pathways in my left arm ruptured three times. Tobirama spent three all-nighters stitching them back together. Also, don't fuse sage chakra on an empty stomach in the early stages. You'll faint. Really faint. So badly that when you wake up, you'll find yourself lying in the Wet Bone Forest with a slug still stuck to your face."

Shinichi snorted with laughter. The God of Shinobi's training advice actually included "soak in hot springs" and "don't train on an empty stomach." He read the passage twice and silently committed the part about hot springs to memory. Then he turned to Tobirama's annotations. Tobirama's handwriting was noticeably neater, with deep pen pressure and almost perfectly uniform spacing between every character, carrying the distinctive rigor of a scientific madman. He had added red notes beside every stage of Hashirama's, his tone gradually shifting from supplementation to snark. Beside the first stage, he wrote: "When my brother's regenerative ability first manifested, he snapped every bandage hanging on the clothesline at home." The annotation beside the second stage was longer: "I once attempted to assist chakra pathway expansion by externally injecting Water Release chakra. Three failures. All test subjects developed chills. Conclusion: this method is specialized for the Senju bloodline. Non-Senju Clan members are forbidden from using it." At the end, he added a much smaller line: "Success rate improved somewhat after diluting it with slug mucus a fourth time. The cost was an entire room covered in slime."

Shinichi could practically imagine Tobirama's expression as he leaned over the table and wrote those words—blank-faced, while inwardly furiously complaining about his unreliable older brother. One brother was passionate and uninhibited, the other calm and restrained, yet together they had left behind this precious legacy in their own ways.

He turned to the final page. Tobirama had written one line at the end of the entire text in red ink. There was no seal, but the handwriting itself carried more weight than any seal: "Senju Clan legacy. Dissemination forbidden outside times of war. —Tobirama."

Shinichi solemnly wrapped the notebook again and placed it inside his clothes. His Sage Body was currently in transition between the first and second stages—his bloodline had awakened, and his sage foundation was being forged. The core condition noted for the second stage was "external stimulation to broaden the chakra pathways," which happened to correspond to the Slug Sage Art chakra he had just fused with. Hashirama had said not to rush, while Tobirama had said diluted slug mucus could be used as assistance. Perfect. The split slug body was not far away.

After putting the copper plate into the inner pocket of his ninja tool pouch as well, he stood and bowed deeply toward the stone door. This was probably the first time anyone without a blood relation had bowed to those two stone statues. But who cared? If Hashirama and Tobirama were watching from above, one would probably laugh and say, "Don't be so formal," while the other would say with a blank expression, "Put the notebook away properly. Don't lose it."