Tsunade spoke only after noticing Kawakaze's unconcerned expression. "It sounds simple, doesn't it?" she said. "But I haven't even told you about the dangers involved."
This wasn't the first time Tsunade had heard Katsuyu speak about Senjutsu. Katsuyu seemed pleased by her interjection and quietly waited.
Kawakaze, seeing the seriousness on Tsunade's face, adjusted his own demeanor.
He recalled from the original story how training in Senjutsu at Mount Myōboku involved risks like turning into a frog or petrifying. Naruto had even relied on two toads and their sticks to avoid disaster. He had assumed Katsuyu's warning—"None survived"—was just an exaggeration.
But judging by Tsunade's expression, the truth seemed far grimmer.
"Tell me. I'm listening," Kawakaze said, his voice steady.
Tsunade hesitated before explaining, her face visibly pale. "The training process for Senjutsu in the Shikkotsu Forest is irreversible. If you fail to transform your Senjutsu Chakra properly…"
"The consequence is turning into a pool of pus."
Her words struck like thunder. It was clear this wasn't just a theoretical danger; Tsunade had likely witnessed it firsthand.
Kawakaze's usual composure wavered. This was truly a gamble with one's life. No wonder Hashirama Senju was hailed as the God of Shinobi—mastering this must have taken unimaginable resolve.
Sensing his hesitation, Katsuyu broke the silence, her voice calm yet commanding. "Though the Shikkotsu Forest's Senjutsu is indeed dangerous, its power is unparalleled. Allow me to elaborate."
"The Senjutsu of Mount Myōboku, while potent, cannot be sustained for long and requires significant preparation."
"The Senjutsu of Ryūchi Cave grants immense power, but it also bestows the user with snake-like characteristics."
"In contrast, the Shikkotsu Forest's Senjutsu preserves a perfect appearance, leaving behind only a few minor Seals. It greatly enhances Chakra and Physical Energy recovery and allows for the autonomous absorption of Natural Energy."
"In simple terms," Katsuyu continued, her tone brimming with pride, "as long as you can absorb Natural Energy quickly enough, you can maintain Sage Mode indefinitely."
Katsuyu's words carried such confidence that even an outsider would have believed her technique to be unrivaled. If not for her calm demeanor, she might have declared outright, 'All other Senjutsu are inferior.'
Hearing this, Kawakaze felt a deep yearning stir within him. No wonder Hashirama Senju's Sage Mode was so fearsome—paired with his Wood Release, it became unstoppable.
"Are there any auxiliary measures?" Kawakaze asked cautiously, hoping for some life-saving fallback.
"Yes," Katsuyu replied, her tone steady and assured.
"What kind of support?" Kawakaze's face lit up with relief. If he had a safety net, he could push forward without fear.
"I can use a clone to heighten your sensitivity to Natural Energy," Katsuyu explained. "However, should you fail, the speed at which you turn into pus will increase significantly. This way, you will suffer less."
Her calm delivery made it sound like an ordinary fact.
Kawakaze was stunned into silence.
...Excuse me? How can you say that? The speed at which I turn into pus will increase?"
Serious, how can you say that?
"Why don't we just forget about it?" Tsunade pleaded, her voice filled with concern. "Even without practicing Senjutsu, you're already very strong."
"I won't be satisfied until I've tried," Kawakaze replied firmly. He understood that in the later stages of Naruto story, without special abilities, he'd be nothing more than cannon fodder. Mastering Senjutsu was just the first step. Without it, he couldn't protect himself, let alone his family.
Tsunade's eyes turned red, and she tightly clutched his sleeve. "Think carefully. If you fail, you'll die—right in front of me."
"Trust me." Kawakaze gently patted her head, managing a faint smile. "With you by my side, I'll succeed."
Turning back to Katsuyu, he asked, "Lady Katsuyu, how do we begin?"
Once his decision was made, Kawakaze didn't hesitate. He feared that lingering too long might sap his courage.
"We can start at any time," Katsuyu replied, her calm voice echoing through the cave. "Follow my instructions."
"Sit cross-legged, place your hands on your lap, palms facing upward."
"Are you teaching me to meditate?" Kawakaze muttered.
"Don't talk," Katsuyu retorted. "Calm yourself first. Breathe deeply, exhale slowly."
If it weren't Katsuyu herself instructing him, Kawakaze might have thought some qigong master was playing a prank.
Once his mind settled, Katsuyu continued. "Mobilize your Physical Energy and Spiritual Energy, and let the two merge into one. Slowly sense the Natural Energy in the air. Try to connect with it, fuse the three forces, and achieve balance."
Kawakaze followed her guidance, gradually entering a meditative state. Katsuyu's countless tiny clones detached from her body and surrounded him, swarming until they completely enveloped him.
Tsunade's heart clenched. From her perspective, Kawakaze had disappeared, replaced by a pulsating mass of tiny Katsuyus. Her worry was palpable.
Within the swarm, Kawakaze focused, reaching out to the Natural Energy around him. A cold, sticky sensation crept over his body, a clear indication of Katsuyu's unique assistance.
The energy he sensed earlier now surged more powerfully. The fusion process was noticeably faster.
The first strand of Natural Energy merged successfully. Then the second. And the third…
But just as Kawakaze began to feel a sense of triumph, a sharp pain exploded through his body. His skin started to rot, the corruption spreading rapidly.
The tiny Katsuyu clones detached from his body where the decay occurred, sliding off like liquid, unable to maintain their hold.
Tsunade's eyes widened in horror as she took in the shocking wounds covering Kawakaze's body. Trembling, she covered her mouth, tears streaming down her face. Yet all she could do was stand there, paralyzed.
She knew she couldn't intervene—introducing her Chakra into Kawakaze's body would only destabilize the process further, causing his body to disintegrate faster.
Kawakaze, for his part, was gripped by fear. The fusion of Natural Energy was accelerating, but so was the unbearable pain tearing through him.
He wanted to scream, but his throat seemed paralyzed; no sound would come.
As he teetered on the brink of despair, preparing for death, fleeting thoughts filled his mind.
Tsunade—I haven't even gotten a taste of her yet.
Kakashi… I haven't even met him yet.
Sakumo… hasn't even been depressed to death yet.
Deep within him, his cells seemed unwilling to surrender. As though refusing to let his vision fade, his body began fighting back against the invasive Natural Energy. His cells surged with vitality, fiercely repairing as they integrated the foreign energy.
Tsunade noticed the shift immediately. The gaping wounds on Kawakaze's body began to close, and the smaller injuries had already healed completely.
Seeing this glimmer of hope, she dried her tears, clasped her hands together in silent prayer, and stared intently at him. She wished with all her heart for the healing to quicken, praying for the next moment to reveal a healthy Kawakaze standing before her.
Kawakaze, too, felt the surge of vitality from within. His cells worked tirelessly, repairing the damage even as the fusion process continued. Slowly but surely, the Natural Energy within him was reaching equilibrium.
Lady Katsuyu, observing the scene, was stunned. For most, the corrosive effects of such an unbalanced fusion were entirely irreversible. Yet Kawakaze's miraculous self-healing ability was not only counteracting the ablation—it was keeping pace with it.
In disbelief, Katsuyu thought, If this continues, he might truly become the second person to master the Senjutsu of the Shikkotsu Forest.
Time crept by as Kawakaze's body endured repeated cycles of ablation and recovery. His flesh was riddled with holes, and the once-numerous Katsuyu clones had all fallen away.
Tsunade could barely recognize the person in front of her. The once-handsome face was now unrecognizable, marred by wounds and scars.
Then, slowly, red seals began to appear around Kawakaze's eyes, forming intricate patterns. His body stopped deteriorating. The backlash of Natural Energy had ceased.
He had succeeded.
"I… succeeded," Kawakaze rasped, opening his eyes to reveal pupils glowing a striking gold. His voice was hoarse, but his words carried undeniable triumph.
Tsunade threw her arms around him. But before he could say anything more, Kawakaze's body gave out, and he collapsed into unconsciousness.