After Tsubasa began frantically using the natural power of heaven and earth to train his body, his family was frantic with worry. At first, only his palms swelled, and everyone could still force themselves to remain calm and composed. But as little Tsubasa furiously fused with the specks of light, different parts of his body began to swell. Sometimes his entire back bulged as though he were carrying a small hill; sometimes an entire leg grew twice as thick, making it difficult for him to move; and sometimes an entire arm swelled as though it had been inflated. The swelling made him look as if he had been stung by countless hornets, a particularly frightening sight. His face was especially distressing: his eyes swelled until they were mere slits, and his lips looked like two greasy sausages hanging from his face. Seeing this, Senju Yasuhei was beside himself with worry. His eyes filled with anxiety and his brows knotted tightly, he rushed about everywhere, begging people to treat Tsubasa.
Three months passed in the blink of an eye. Famous experts from the clan and renowned doctors from various countries all came to see him, but none of them could do anything about little Tsubasa's strange symptoms, and they could find no cause at all.
In the end, the matter came to the attention of the Hokage, despite his busy schedule. Konoha had only just been established, and with the major shinobi clans and ninja gathered in a single village, conflicts kept arising. There had even been numerous assassinations. The Hokage, Hashirama Senju, had countless matters to handle every day and was run off his feet. One day, he happened to overhear members of his guard discussing the matter and learned of the strange occurrence in the Second Elder's family.
That night, Hashirama Senju made time to bring Tobirama Senju along, and the brothers came to investigate together. When Senju Yasuhei's family saw the Hokage and his brother arrive, it was as though they had glimpsed dawn in the darkness, and their eyes shone with hope. Senju Yasuhei gave them a reception of the highest order, and the whole family respectfully waited to welcome them. After exchanging a few brief pleasantries, Hashirama and Tobirama got straight to the point and began carefully examining little Tsubasa's condition.
Tobirama Senju was a renowned sage of the Senju Clan, and Hashirama Senju was known as the God of Shinobi. Yet even after a careful examination, they found the rare condition extremely difficult to deal with and had no good solution. Still, Tobirama Senju and Hashirama Senju reached a diagnosis: little Tsubasa's body could fuse with the natural energy freely dispersed between heaven and earth. Fortunately, he absorbed very little of it, and it remained only on the surface of his skin, which was why he merely swelled up. The Senju Clan's secret medicine could quickly cure the swelling, but it could not stop Tsubasa from absorbing natural power himself.
In the end, Hashirama Senju told Senju Yasuhei, "We've never encountered a case like little Tsubasa's, but that doesn't necessarily mean it's a bad thing. We can see that he's slowly adapting to natural energy, though it's hard to say how long that will take. It could be a year, ten years, or even his whole life. But as long as he adapts, he'll definitely be able to train in Sage Mode when he grows up. Throughout history, only a handful of people have truly mastered Sage Mode." As Hashirama Senju spoke, a hint of anticipation appeared in his eyes, as though he could already see little Tsubasa mastering Sage Mode in the future.
As Hashirama Senju left, he also said he was willing to take little Tsubasa as his disciple when he grew up. He left behind a hundred million ryo to help pay for the Senju Secret Medicine Tsubasa needed to counter the natural energy. A single dose of the Senju Secret Medicine was worth a million ryo. Although it could not bring the dead back to life, it could heal serious injuries, and it was unavailable on the market at any price. Someone in Tsubasa's condition needed it every day. When Senju Yasuhei heard this, his eyes instantly grew wet and his heart filled with gratitude. His lips trembled as he tried to offer thanks, but he was too overwhelmed to speak. All he could do was bow deeply to express his gratitude.
After seeing the brothers Tobirama and Hashirama off with tears of gratitude, Senju Yasuhei finally understood the cause of little Tsubasa's condition and how to deal with it. He immediately began gathering the various precious medicinal ingredients needed for the Senju Secret Medicine and set about preparing it.
Senju Tenpuku and his six sisters-in-law also began running various businesses in Konoha. Tsubasa's first aunt opened a large restaurant in a prime location in Konoha, his second aunt opened an inn, his third aunt opened a clothing store, his fourth aunt opened a hot spring entertainment establishment, his fifth aunt opened a winery, his sixth aunt opened a casino, and Senju Ga opened a weapon shop. Senju Yasuhei opened a pharmacy, and Senju Tenpuku became a member of the Hokage's guard. For the sake of little Tsubasa, their "gold-swallowing beast," the entire family put all their energy into earning money to prepare the secret medicine. Everyone knew that although the road was full of hardship, it was all worthwhile for little Tsubasa's future. Their eyes shone with determination and resolve.
With his family's full financial support, little Tsubasa could recover with the help of the secret medicine by the next day, no matter how badly he was injured. With that assurance, he trained his body with natural energy even more desperately. Over three months, he tempered his skin to perfection, until the specks of energy could no longer harm it and it had fully adapted to natural energy. Little Tsubasa was filled with a sense of accomplishment. Although the process was painful, every breakthrough brought him one step closer to his goal.
After he finished tempering his skin, the specks of energy began to fuse into his flesh. The pain of his muscles tearing and reforming was like being burned alive, far more than an ordinary person could bear. A trace of doubt and worry rose in little Tsubasa's heart. He had a strong feeling that the immortal cultivation method he was using definitely was not a proper Taoist method. It was far too brutal and bloody. If I didn't have an adult's soul, who could endure this? But he had no better option, so he could only grit his teeth and steel himself to continue. Fortunately, the secret medicine his mother gave him was effective. No matter how badly he was hurt, he could recover by the next day. That reassured him somewhat, and whenever the pain became unbearable, the thought of the medicine's support gave him the courage to keep going.
Every day, little Tsubasa refined all the flesh in his body with natural power. After each round of refinement, he could clearly feel his strength undergoing tremendous changes. Although he gained great strength, he also endured immense pain every day. His face often twisted in agony, and cold sweat constantly beaded on his forehead.
Little Tsubasa's family faced immense financial pressure. During the skin-training stage, one dose of the Senju Secret Medicine could last two days. Now that he was training his flesh, one dose lasted only a day. The cost had instantly doubled, and they had to spend a million ryo on little Tsubasa every day. Just like that, six months passed in a flash, and little Tsubasa finally tempered his flesh to perfection. By then, the amount spent on him had reached two hundred million ryo. Little Tsubasa's title of "Gold-Swallowing Beast" also spread throughout Konoha. Although his family was under tremendous pressure, seeing little Tsubasa grow and progress made them feel that every sacrifice was worthwhile. Still, in the occasional quiet of late night, they felt a trace of concern about their future finances.
After natural power finished transforming his flesh, little Tsubasa began tempering the sinews and bones throughout his body. At the start, the pain that penetrated to his very marrow made Tsubasa feel as though he were in hell. Every day, he repeatedly passed out from the pain and woke to it again. Little Tsubasa kept encouraging himself. He did not know how he had made it through, but every time he woke from the agonizing pain, he told himself to persevere. Under this repeated torment day after day, little Tsubasa's willpower was tempered to an extraordinary degree, and his soul grew stronger, transformed, and ascended every day. If expressed in numbers, then if newborn little Tsubasa's soul strength had been ten, it was now at least a thousand. It took little Tsubasa a year to temper his sinews and bones to perfection. Nearly every day, he needed the secret medicine to stay alive, and the money spent reached a staggering five hundred million ryo. Notably, after he finished tempering his sinews and bones, little Tsubasa's skull had completely closed. By this time, when Tsubasa entered his state of clarity, he could no longer sense that colorful world. He could only sense two kinds of natural power, black and yellow. This left Tsubasa feeling somewhat regretful that he had lost that once-wondrous perception, but also relieved, because it might mean that his cultivation had entered a new stage and gained a clearer direction.
After tempering his sinews and bones to perfection, he began training his organs. Human internal organs were extremely delicate, and a single mistake could endanger his life. Tsubasa was therefore exceptionally careful, his face full of caution and concentration. Drawing on medicine from his previous life, he strengthened his organs according to their functions. He began with the respiratory organs, fusing the black and yellow natural powers into them one at a time. It took him six months to temper his lungs, trachea, and bronchi to perfection. Throughout the process, he constantly worried that something might go wrong. He approached every attempt with great care, silently praying that he could complete it smoothly.
Next, he began tempering his digestive organs: his liver, spleen, stomach, and intestines. That also took six months. Then he tempered his urinary system: his kidneys, bladder, ureters, and urethra. That too took six months. Whenever he completed a stage of tempering, a wave of joy and accomplishment rose in his heart, but he did not dare relax in the slightest, because he knew even harder challenges lay ahead.
Next came tempering his heart and blood vessels, which again took six months. After that, he tempered his reproductive system, including his vas deferens, prostate, and testicles, which also took six months. Finally came the most dangerous parts, his brain and nervous system. It took a full two years to temper them successfully. At this point, he could be said to have successfully completed Body Tempering. Tsubasa had spent nearly six-odd years in total completing the first step of immortal cultivation and bringing Body Tempering to perfection.
During those six and a half years, countless people urged the Second Elder's branch of the family to give up on little Tsubasa. Senju Tenpuku and Senju Ga also had their second son, Tenmei, in Konoha's second year. Yet the Second Elder's branch had never considered giving up on Tsubasa. Their eyes showed their determination and love for him. The whole family emptied its coffers to prepare the Senju Secret Medicine, spending what could only be described as an astronomical sum. Tsubasa consequently earned the title of Konoha's "Gold-Swallowing Beast."
Under Hashirama Senju's leadership, however, the Senju Clan showed an unprecedented spirit of unity, affection, and mutual support. They generously contributed money, some giving a few million ryo and others giving over a hundred million. The reserves of a great clan with a thousand years of history were terrifying indeed. Only through this did Tsubasa ultimately make it through his arduous six-and-a-half-year journey of body training.
No wonder the immortal cultivation novels of his previous life all said that cultivation depended on wealth, companions, land, and methods, with wealth ranked first. Wealth meant money and cultivation resources; companions meant fellow cultivators, cultivation partners, and backers; land meant blessed grotto-heavens; and methods meant cultivation techniques, aptitude, and comprehension. In this life, the very first step of immortal cultivation, body training, had emptied the family's coffers. That showed just how difficult immortal cultivation was. Little Tsubasa was filled with emotion, both looking forward to and feeling apprehensive about the cultivation path ahead.