Training day

As night fell, Shikai lay by the campfire, gazing at the stars. The day's battle and Tsunade's lessons were swirling in his mind.

"Tsunade-san..." he said suddenly, "Have you ever had to transfer all your chakra to save someone?"

Tsunade, sitting by the fire, remained silent for a moment. "Yes. And sometimes, it almost cost me my life. But as a medical ninja, it's a sacrifice you must be prepared to make. Every life you save makes you stronger, Shikai. Remember that."

She spoke those words while thinking of someone specific.

...

The two travelers entered a region covered in an immaculate white blanket. The biting wind whistled between the mountains, and each breath formed a cloud of condensation. Shikai watched Tsunade, who advanced with an impressive calmness despite the cold.

"How do you manage not to shiver?" he asked, his teeth chattering slightly.

Tsunade turned with an amused smile. "It's not just a matter of habit. Using your chakra to regulate your body temperature is an essential skill, especially for a ninja operating in extreme environments."

Near a small cave they had found for shelter, Tsunade explained the basics to Shikai.

"Chakra is not just a source of energy for techniques. It can also be used to influence your own body. You can direct it towards your circulatory system to generate heat or, conversely, disperse it to cool down in a desert."

Shikai furrowed his brows. "It sounds similar to the precise chakra control you taught me for medical techniques."

Tsunade nodded. "Exactly. Except here, you're not healing, you're maintaining. Try to visualize your chakra as an inner flame. Make it grow slowly."

...

In the evening, after an exhausting day of training, Tsunade announced that she was heading to the nearby village to relax. "I'll see if I can find a tavern. Don't get into any trouble while I'm gone."

Shikai watched her leave with an amused sigh. "I should be the one saying that to you."

Sitting under a clear sky, Shikai closed his eyes and let his mind wander. He thought back to everything he had learned so far: precise chakra control, medical techniques, Tsunade's version of taijutsu, and now adapting Tobirama's Suiton techniques.

Taking out a blank scroll and a brush, Shikai began working on a complex fuinjutsu he had been studying in secret. Inspired by the ultimate Uzumaki technique passed down by Kushina, he aimed to create a seal capable of trapping someone, forcing them to follow his orders. Or perhaps a technique to ensure he would never be betrayed.

...

Late at night, Tsunade returned to the campsite, slightly tipsy. She stumbled near the fire, a playful smile on her face.

"So, kid, you didn't burn down the camp in my absence?" she joked.

Shikai, still immersed in his scrolls, raised his eyes. "No, but I assume you lost some money gambling."

She laughed. "It's not important. What matters is that tomorrow, you'll have a new lesson. Get ready, it won't be easy."

Shikai shook his head with a mischievous smile. "As usual, then."

...

In an isolated village nestled in the heart of the mountains, Shikai and Tsunade had stopped for a few days. The village was peaceful, and the inhabitants lived modestly but were welcoming, offering shelter to their two visitors in exchange for medical care provided by Shikai.

Shikai also used this time to perfect his techniques and, most importantly, to continue selling his explosive scrolls on the local market. Thanks to his discretion and business acumen, he had accumulated a small fortune of 5 million ryōs, while secretly placing Hiraishin seals at strategic locations in each village he visited.

That day, Tsunade decided it was time for Shikai to learn an advanced-level technique: *Ranshinshō*.

Tsunade took Shikai to a clearing away from the village. The air was fresh, and the sound of birds echoed around them.

"The Ranshinshō, or Neural Signal Disruption, is a complex medical ninjutsu technique. It allows you to disrupt your opponent's neural signals, reversing their movements. An arm rises when they want to lower it, a leg steps back when they want to advance. It's extremely destabilizing in combat."

Shikai nodded, focused. "I understand the concept."

Tsunade crossed her arms. "You'll need to channel your medical chakra in a targeted manner and inject it at the right moment. Now, try it on me."

Shikai hesitated. "On you? But if I mess up..."

Tsunade laughed. "Trust me, kid, you're not going to seriously affect me. Come on, show me what you can do."

...

Later in the day, Tsunade decided to test Shikai's abilities in a real combat situation.

"Show me what you're worth now," she said with a mischievous smile.

Shikai stepped back, surprised. "A fight with you? You'll crush me."

"It's not about winning or losing," she replied. "It's about showing what you've learned."

Shikai assumed a defensive stance as Tsunade charged with impressive speed. She struck with her fist, but Shikai barely dodged, his simple speed boosted by the activation of his cells. He repositioned himself behind her.

Shikai followed up with the **Ranshinshō**, targeting Tsunade's shoulder. The strike landed, but she broke the effect by forcing her chakra to flow through her nerves.

"Do you really think this little trick will work on me?" she asked with a mocking smile.

For a moment, she seemed immobilized.

"Not bad at all, Shikai," she said, gritting her teeth. "But it's not enough!"

With an explosion of power, she sent a shockwave that pushed Shikai back several meters.

Despite the power difference, Shikai remained undeterred. He channeled his chakra into his fists, using the **Enhanced Chakra Strength** technique Tsunade had taught him.

Shikai, as quick as lightning, threw the first punch. He rushed towards Tsunade with a series of rapid and precise punches, hoping to take his opponent by surprise. His fists descended upon Tsunade, but she, with surprising agility, dodged each strike with fluid grace. Her movements were so swift they seemed almost blurred.