Upon hearing those words, Naruto stood frozen in place. His mind struggled to process the weight of the claim as his eyes stretched wide with disbelief.
You're my father? Naruto asked, his voice cracking. Wait, that can't be right! You look exactly like me! You're the same age!
I ended up in this world by accident due to a specific Space-Time Ninjutsu, Minato explained calmly. Perhaps it's the nature of space and time itself, or maybe the flow of time just moves differently between parallel dimensions. In the world I come from, I'm still living decades in the past.
But your last name is Namikaze, Naruto countered, still searching for a flaw in the logic.
And your mother's surname is Uzumaki, Minato said, his voice softening into a gentle, practiced tone. Her name is Uzumaki Kushina. She has the most beautiful red hair you could ever imagine.
Naruto stared blankly at Minato. The wall he had built around his heart for years began to crumble. Tears welled up in his eyes, blurring his vision before they finally spilled over.
He quickly wiped his face and let out a heavy, shaky sniffle. If what you're saying is true, then you really are my dad. I'm not just some kid without parents. And I'm not a monster either.
Of course you aren't, Minato replied. You're my son. You're the son of the Fourth Hokage.
Minato finished drying his hands on a towel. He took a couple of steps forward and reached out, gently patting Naruto's head. Inside, his thoughts remained cold and detached, observing the boy's emotional breakdown with the curiosity of a scientist.
Don't do that, it's weird, Naruto mumbled, shyly pulling away from the touch.
Even though he was overwhelmed with the emotion of finally meeting his father, the physical reality was jarring. Seeing a version of his father who looked like a peer made the situation feel incredibly surreal.
I see, Minato thought for a moment. Give me a second, then. I'll change how I look.
He turned and walked into the bedroom, pulling the door shut behind him. Naruto waited in the silence of the messy apartment, his heart racing.
Less than two minutes later, the door creaked open.
A tall, striking man with blond hair appeared. He looked to be in his early twenties, possessing a commanding presence that filled the small room. Naruto instinctively took two steps back, his jaw dropping as he took in the transformation.
The man wore a simple black undershirt and matching trousers. His facial features were refined and handsome, essentially a more mature and sharpened version of the younger Minato. The youthful softness was gone, replaced by the sharp lines of a grown man.
This wasn't a simple Transformation Technique. It was the power of Minato's right eye, the ocular jutsu known as Minakanushi. This ability allowed him to manipulate the physical growth state of a target.
This was the first time Minato had used the eye on himself. He noted internally that the ocular power consumption was nearly $0\%$ for his current reserves. However, he calculated that using it on others would likely require a much larger expenditure of energy.
Back when he had first unlocked this power, Minato had prepared for such a situation. He had purchased several sets of clothing in various sizes to keep in his storage, and they were finally proving their worth.
Yes, this is how I would look if I had grown naturally to twenty, Minato said, a faint smile on his lips. My face should be identical to the man you see on the monuments.
Naruto looked at him in awe. You look exactly like the Fourth on the Hokage Rock.
That's because we're the same person from different worlds, Minato said. He reached out again and patted Naruto's head. It's not so strange now, right?
Yeah, Naruto whispered. His eyes turned red again, but this time he didn't pull away. He just gave a small, muffled nod of agreement.
Then... are you going to leave later? Naruto asked, the fear of abandonment creeping back into his voice.
I have to return to my own world eventually, Minato said with a nod. But I won't leave yet. Before I go, I'm going to teach you Ninjutsu. I'll make sure you grow as strong as possible as quickly as you can.
Naruto looked down, disappointed but not entirely surprised. He understood that this man didn't belong here. He was a visitor from another timeline, and it was impossible for him to stay forever.
Seeing the boy's spirits sink, Minato felt a rare moment of genuine pity. I'll make you a promise. Before I leave this world, I'll find a way to let you meet your actual parents.
Really? Naruto asked. A brilliant light returned to his eyes, though it flickered with doubt. Don't lie to me. They've been dead a long time.
Death isn't much of a hurdle for me, Minato said, rubbing the boy's head. I am very strong, Naruto.
Mm-hmm, Naruto said, pressing his lips together. A spark of hope began to grow in his chest.
The following morning, Minato and Naruto arrived at the Third Training Ground just as the sun began to rise. They were there to continue the grueling training for the Rasengan.
Yesterday, Naruto had managed to maintain $2,000$ Shadow Clones without collapsing from exhaustion. Seeing that this wasn't a heavy burden, Minato decided to push him further, instructing him to increase the number of active clones to $4,000$.
You have to keep the core concept in mind, Minato explained. The Rasengan requires you to make your Chakra rotate in a completely chaotic way inside the sphere. Simple, uniform rotation won't cut it, but most people can only manage to control rotation in one direction at a time.
Minato watched as the sea of clones began to work.
You can take a shortcut by using a second hand to add more force, but that ruins the utility of the move, Minato continued. It's not worth the trade-off. Use both hands for now to understand the feeling of the friction. Then, try to let go right before the water balloon pops. You need to adapt to the pressure bit by bit.
Minato shared the nuances of his own training history, and Naruto threw himself into the work with singular focus.
Two hours of intense labor passed. Minato signaled for Naruto to dispel the clones. The sudden rush of memories and fatigue hit the boy, but he remained standing.
Now, try it again, Minato commanded.
Okay! Naruto shouted.
He gripped his right wrist firmly with his left hand, balancing the water balloon on his right palm. He closed his eyes, focusing on the chaotic swirl of energy. Suddenly, the balloon deformed violently, twisting in multiple directions until it burst with a loud pop.
Minato's eyes narrowed slightly. He was impressed. Naruto's natural talent for this specific type of training seemed even higher than Nawaki's.
Poor Nawaki, Minato thought to himself. He can't even compare to my son.
Well done, Minato said aloud, his voice warm and encouraging. He pulled a solid rubber ball from his pouch. Now we move to the second stage. You need to burst this in the exact same way.
Another ball? Naruto groaned. He felt exhausted, but he took the ball anyway. He couldn't help but complain as he looked at the dense rubber. By the way, isn't there any other Ninjutsu you can teach me besides this?
You don't seem to have much of a talent for Hand Signs, Minato said bluntly. You aren't really built for the path of a standard ninja.
As he spoke, Minato raised one hand. His fingers moved with a blurring speed, weaving signs so fast they left afterimages in the air. My personal limit is $8$ signs per second. What is your record?
Naruto looked away, rubbing the back of his neck guiltily. About... $3$.
For a ninja, that's basically being a cripple, Minato said with a light chuckle. The Rasengan is an A-rank Ninjutsu. If you add Nature Transformation to it later, it becomes S-rank. Most importantly, it requires no signs at all. It's perfect for a... simple person like you.
You were going to say idiot, weren't you? Naruto asked. He squinted his eyes and glared gloomily at Minato.
Minato just offered an embarrassed, boyish smile in response.
But what does an S-rank Rasengan even look like? Naruto asked, his curiosity getting the better of him. Do you know how to do it?
Of course I do. I created the technique, Minato said.
He raised his palm. Chakra began to swirl and condense at an incredible rate. Within seconds, a massive sphere of energy appeared, surrounded by four rotating blades of high-frequency wind.
The sheer pressure of the technique kicked up a violent gale that flattened the grass for several meters. Hidden in the trees nearby, Kakashi felt his breath catch in his throat. His eyes widened in pure shock.
He's already perfected it? Kakashi thought. And he did it with one hand?
To perform a standard Rasengan with one hand was impressive enough. To do it without signs and simultaneously infuse it with a perfect Nature Transformation was a feat that defied logic.
Is that level of Chakra control even humanly possible? Kakashi wondered.
Just then, Minato raised his other hand. A second orb began to form, but this one glowed with a brilliant, scorching red light.
This is the Wind Release: Rasenshuriken, and this is the Fire Release: Great Flame Rasengan, Minato explained. Both are advanced forms of the original move.
Because he was showing off for his son, Minato's tone carried a hint of pride. What do you think? Is it impressive?
That's so cool! Naruto yelled, clenching his fists. He looked like a devoted fan watching his idol.
Observing from the shadows, Kakashi frowned. He felt a sense of cognitive dissonance. That doesn't really sound like the naming style Sensei usually uses...
Just as that thought crossed his mind, he heard Minato speak again.
Of course, the formal name would be the Dimensional Inspiration-Inspired Great Flame High-Explosive Rasengan.
Ah, Kakashi thought, nodding to himself. That's more like it.
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