Compared to other A-rank Ninjutsu, the Rasengan is actually much harder to Cultivate.
If Ninjutsu is compared to a math problem, then Hand Seals are like the calculation process on scratch paper; one just needs to follow the steps to derive the answer.
Cultivating the Rasengan is like discarding the scratch paper and arriving at the answer directly through mental calculation.
As for adding Nature Transformation to the Rasengan, it's like interdisciplinary Fusion and requires mental calculation; it's simply not something an average person can do.
It's worth mentioning that although the cultivation method for the Rasengan is difficult, the principle behind it is quite simple.
To put it bluntly, it's kneading a ball—literally kneading a ball!
It can be seen as a math problem with a simple concept but requiring complex mental math, which is exactly the opposite of Ninjutsu that relies on Hand Seals.
Techniques like the Flying Thunder God and Living Corpse Reincarnation are like Qian Xuesen's manuscripts; even if they are placed right in front of you, if you don't understand them, you just don't, and if you can't learn them, you just can't.
Whereas Advanced Ninjutsu like the Rasengan and Tailed Beast Ball are like manufacturing an Atomic Bomb; the principle isn't that complex, but the actual production is extremely difficult.
Kakashi's assessment of the Rasengan as 'the ultimate in Chakra shape transformation' is by no means an exaggeration.
Nawaki was able to master Tree Climbing within two hours, which shows that his talent for Chakra control is not bad and should meet the requirements for cultivating the Rasengan.
Watching Nawaki walk unsteadily on the water's surface, Minato smiled knowingly and turned into the kitchen to prepare lunch.
Water Surface Walking is an Advanced technique of Tree Climbing, adding only a step of real-time Chakra adjustment; with Tree Climbing mastered, it should only take a few more tries to get the hang of it.
Sure enough, before Minato finished cooking, Nawaki's cheers came from the courtyard.
"I did it!"
"Let's increase the difficulty for him."
Minato said without looking back, and the Clone cutting vegetables beside him turned and walked out of the house.
"Minato! Look! I succeeded!"
In the small pool in the courtyard, Nawaki stood steadily on the water's surface with both feet. Seeing the Clone arrive, he called out excitedly.
Seeing this, the Clone nodded with a hint of a smile: "The main body sent me to increase the difficulty for you."
Saying that, he crouched down and pressed one hand on the water; instantly, turbulent waves surged!
"Whoa—"
As the waves churned, the Chakra under Nawaki's feet immediately lost balance, and with a splash, he fell into the water.
"When you can walk freely on waves, you can start cultivating the Rasengan," the Clone said with a smile.
"Dammit... I was just careless! Just you wait, I'll master it for you to see right now!"
Nawaki scrambled up, wiped the water off his face, and tried to stand on the water's surface again.
By the time Minato finished lunch, Nawaki could barely stand steady in the waves, though moving was still a bit difficult.
"Time to eat."
Minato called out to the courtyard while holding the dishes.
Hearing this, Nawaki rushed into the house like a whirlwind, changed out of his wet clothes, and sat at the table to devour the food.
After eating, he rushed back into the courtyard to continue his Water Surface Walking cultivation.
Soon, another two hours passed.
Nawaki walked leisurely on the water's surface; no matter how the waves churned beneath his feet, they couldn't affect him in the slightest.
"I succeeded..."
Nawaki's tone couldn't hide his excitement, feeling like his hard work had finally paid off.
"Congratulations, you can start your Rasengan cultivation."
The Clone said with a smile, then vanished with a 'poof'.
Meanwhile, Minato was memorizing the hand seal gestures for Earth Release Ninjutsu in his room. After receiving the Clone's memories, he got up and walked out.
Just as he reached the courtyard, he saw Nawaki sitting on the Engawa, gently rubbing his ankles and hissing in pain.
"Sss—it hurts!"
"You overexerted your Chakra."
Minato chuckled: "It's not a big problem, but to prevent any lasting issues, you should go to the hospital. Sensei should be there right now."
Recently, the border near the Land of Rain has been unstable, and wounded are sent back every few days, which has led to a shortage of staff at the hospital.
Tsunade's Ninja assignment isn't at the hospital, but because of her outstanding medical expertise, she is often invited to help out.
Interestingly, because of this connection and her status as the First Hokage's granddaughter, plus her beauty, she has more say at the hospital than the Director.
"It's fine, I'll just have my sister check it when she gets home."
Nawaki said urgently: "Let's hurry and start the Rasengan cultivation!"
Minato shook his head: "Then we definitely need to go out; I need to buy some props to help with your cultivation."
"Alright..."
Nawaki looked quite uninterested.
He changed into clean clothes, and as the two were heading out, they saw Tsunade walking toward the house with a red-haired girl.
"Sister!"
Nawaki waved at Tsunade.
Minato's gaze fell on the girl beside Tsunade.
The girl had red hair as bright and vivid as fire, a round face with baby fat, and a pair of large, dark, spirited eyes.
"Where are you two going?" Tsunade asked as she saw them leaving.
"Nawaki overdid it with Water Surface Walking, and the Meridians in his ankles are a bit sore. I was planning to take him to the hospital to find Sensei," Minato said.
"Oh?"
Tsunade crouched down, squeezed Nawaki's ankles, and then stood up again: "It's not a big deal; it'll be fine after a night's sleep."
"But I didn't expect you to already be practicing Water Surface Walking, Nawaki. Minato taught you, right? How's the progress? Have you learned it?"
"Of course!"
Nawaki crossed his arms and lifted his chin proudly: "I can already walk freely in waves!"
Hearing this, Tsunade rubbed Nawaki's head with a smile: "Is that so? That's impressive!"
Nawaki turned his head away awkwardly, not letting Tsunade touch his head: "Don't treat me like a kid!"
"But you are a kid~"
Tsunade chuckled, then gently placed her hand on the girl's shoulder.
"By the way, let me introduce you. This is the child I mentioned before who will be staying with us for a while. Her name is Uzumaki Kushina."
"H... Hello."
Kushina spoke somewhat nervously, a trace of unease hidden in her eyes.
"Oh! Hello! I'm Nawaki! I'm my Older Sister's brother! Please guide me!"
Nawaki gave a thumbs up with a grin and spoke enthusiastically.
"Hello, I'm Minato Namikaze, Tsunade-sensei's Disciple. Nice to meet you."
Minato's gentle smile eased the tension in Kushina's heart a little.
That's more like it... Who in their right mind introduces themselves as their Older Sister's brother?
This blond guy is quite normal, though he looks a bit effeminate, lacking masculinity... Kushina thought to herself.
Although she was uneasy being a newcomer, she actually had a quite lively... even spicy personality.
Seeing that the atmosphere of their first meeting was relatively harmonious, Tsunade looked at Minato with a smile: "Great! To celebrate Kushina's arrival, let's make dinner more feast-like!"
Minato nodded with a smile: "Okay, leave it to me."
Hearing this, Kushina's expression froze slightly.
Eh?
What's wrong with this family?
Why is a kid doing the cooking?
I haven't been sold out by the Village, have I?
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