Naruto: Hero's Fist

The pre-dawn air in Amegakure was thick with mist, the ever-present rain reduced to a fine drizzle. In the yard behind their modest house, three young figures stood at attention, their bodies tense with anticipation and nervousness. Nagato, Yahiko, and Konan watched as Garp paced before them, his massive frame casting a long shadow in the dim light.

"Alright, you little rascals." Garp began, his voice uncharacteristically serious. "Today marks the beginning of your journey to become true warriors. It won't be easy, and there will be times when you'll want to give up." He paused, his eyes scanning each of their faces. "But remember why you're doing this. For your friends, for your safety, and for you to have a chance at peace."

The children nodded solemnly, their resolve evident in their eyes.

Garp's serious expression suddenly broke into a wide grin. "Now then, let's start with a little warm-up! Five hundred laps around the house, go!"

"Five hundred?!" Yahiko exclaimed, his jaw dropping.

"You're right, my boy," Garp nodded sagely. "Make it a thousand! Bwahahahahaha!"

As the children set off on their run, Garp watched them with a mixture of pride and concern.

'I haven't told them about the fact that Konan and Yahiko are nearly immune to physical damage now, but they should figure it out once they start using their abilities. If they want to go out into the world, they'll need to at least be able to pressure someone like me. With the Otsutsuki not walking around yet, they would be safe as long as they have the strength to equal a Kage.' Garp thought.

He did not want to send the three to their deaths where they lived a pitiful fate like in the original timeline.

After he decided to take the three as his Grandchildren, that meant he would do whatever was neccesary to ensure that they lived, even fighting against the world itself if he needed to.

Hours later, as the sun climbed higher in the sky, Garp called the exhausted children to a halt. They stood before him, panting heavily, their clothes soaked with rain and sweat.

"Good work! Now, it's time to focus on your individual training. We'll start with you, Yahiko."

Yahiko straightened up, excitement overriding his fatigue. "Yes, Gramps!"

Garp led Yahiko to a clearing nearby, leaving Nagato and Konan to catch their breath. "The Rumble-Rumble Fruit turns you into living Lightning." Garp explained. "But power without control is dangerous. You need to learn to harness it."

He pointed to a series of metal rods he had set up earlier. "I want you to channel your electricity through these rods, lighting them up one by one. Start small, then gradually increase the power. This will teach you how precisely to control the Lightning, and if you can do this, then Chakra Control will be simple."

Yahiko nodded, his face scrunched in concentration. He held out his hand, willing the electricity to flow. His hand turned into electricity, yet it was constantlu returning back to normal.

"Come on, come on," he muttered, growing frustrated.

"Relax, kid." Garp advised. "Don't force it. Feel the energy within you, let it flow naturally."

Yahiko took a deep breath, closing his eyes. He thought about the crackling energy he had felt when he ate the fruit, the way it had coursed through his body. Slowly, he felt a tingling sensation in his fingertips.

His eyes snapped open as a small bolt of electricity shot from his hand, connecting with the first rod. It glowed briefly before fading.

"I did it!" Yahiko cheered, jumping up and down.

Garp nodded approvingly. "Good start. Now, keep practicing. I want all these rods lit up by the time I get back."

Leaving Yahiko to his task, Garp returned to where Nagato and Konan waited. "Konan, you're up next."

He led the blue-haired girl to another part of the yard where he had prepared a small plot of soil. "The Wood-Wood Fruit gives you power over nature itself." Garp explained. "As I stated, the only known Shinobi who could also do this was the First Hokage. This means you have a goal to surpass in your mind now."

Konan nodded silently, her eyes fixed on the bare earth before her.

"I want you to try and grow a sapling." Garp instructed. "Start by feeling the life force in the soil, then channel your energy into it."

Konan knelt by the plot, placing her hands on the damp earth. She closed her eyes, trying to sense the latent life within the soil. At first, she felt nothing, but as she concentrated, she began to perceive a faint pulse beneath her palms.

Excited by this discovery, she pushed her energy into the ground. Suddenly, a small shoot burst from the soil, growing rapidly into a sapling nearly as tall as she was. Startled, Konan fell backward.

"Oho!" Garp laughed. "Quite the green thumb you've got there! But control is key. Try again, but this time, aim for something smaller."

As Konan set to work on controlling her newfound abilities, Garp turned his attention to Nagato. The red-haired boy stood quietly, his Rinnegan eyes watching Garp intently.

"Now, Nagato," Garp began, his voice softening slightly. "Your fruit is unique. The Human-Human Fruit, Model: Buddha, grants you immense physical power and the ability to transform. But with your Rinnegan, the potential is even greater."

Nagato nodded, a flicker of uncertainty crossing his face. "How do I start, Grandfather?"

Garp placed a hand on Nagato's shoulder. "Begin by looking inward. Feel the power of the fruit within you, and try to draw it out. Don't force a full transformation yet – start with just your arm."

Nagato closed his eyes, focusing on the strange energy he had felt since eating the fruit. He imagined it flowing into his right arm, changing it. To his surprise, he felt his arm growing heavier, larger.

Opening his eyes, he gasped. His right arm had transformed, taking on a golden hue and growing to massive proportions. "I... I did it," he whispered in awe.

Garp beamed with pride. "Excellent work, my boy! Now, try to maintain that form while I test its strength."

For the next few hours, Garp rotated between the three children, guiding their training and pushing them to explore the limits of their new abilities. Yahiko learned to control the intensity of his electricity, Konan practiced growing plants of various sizes, and Nagato worked on partial transformations of different body parts.

As the sun began to set, Garp called the exhausted children together. They stood before him, tired but proud of their progress.

"You've all done well today." Garp said, his voice filled with warmth. "But this is just the beginning. Your powers are strong, but they're only tools. True strength comes from here." He tapped his chest, right over his heart.

"Tomorrow, we'll begin training in Haki." he continued. "It's the power of will, the strength that comes from within. Combined with your Devil Fruit abilities and your ninja techniques, it will make you truly formidable."

The children nodded, too tired to speak but their eyes shining with determination.

"Now then." Garp clapped his hands together, his serious demeanor suddenly replaced by his usual jovial grin. "Who's hungry? I think it's time for a feast!"

As they made their way back to the house, Garp couldn't help but feel a swell of pride. These children, with their incredible potential and unwavering spirits, were the future. He glanced back at the training grounds, where scorch marks, wooden saplings, and oversized footprints marked the day's efforts.

"Watch out, world." he murmured to himself. "These kids are going to change everything."

Inside, as Garp prepared a massive meal (cooking was another skill he'd picked up in this new life), the children collapsed around the table, recounting the day's events with excitement despite their exhaustion.

"Did you see how big my arm got?" Nagato asked, his usually quiet voice animated.

"Yeah, but did you see how I lit up all those rods?" Yahiko boasted, small sparks still occasionally dancing across his skin.

Konan simply smiled, a small flower blooming in her palm before transforming into an origami rose.

As Garp set down plates piled high with food, he couldn't help but laugh. "Bwahaha! Eat up, you'll need your strength. Tomorrow's training will make today look like a picnic!"

The children groaned good-naturedly, but dug into their meals with gusto. As they ate, Garp watched them, his mind already planning the next day's training. 

The rain continued to fall outside, a constant reminder of the world they lived in. But within the warm, noisy kitchen, filled with laughter and the clatter of chopsticks, a new family was forming. A family forged in shared dreams, mutual respect, and the will to change the world.

As the meal wound down and the children's eyelids began to droop, Garp shooed them off to bed. "Rest well," he called after them. "Tomorrow, you three will take another step on the path to becoming True Heroes!!"

The children mumbled their goodnights, stumbling off to their rooms. Garp remained at the table, sipping a cup of sake and reflecting on the day. He thought of his old life, of the Marines and the pirates, of the endless cycle of conflict he had left behind. Then he thought of these children, of their potential to break such cycles. Even in his other life, the world simply seemed to mundane, with him just being an ordinary person in it.

"Sengoku, old friend." he murmured into his cup, "I think I've found something worth protecting in this new world too."

With that thought, Garp finished his drink and headed to bed himself. Tomorrow would bring new challenges, new triumphs, and new steps on the journey to reshape this world of shinobi. And Garp, along with his three young charges, would be ready to face it head-on.

~

In the depths of Konoha, far beneath the bustling streets and cheery facades, lay a chamber shrouded in shadows. Here, in this dimly lit room, Shimura Danzo sat behind a heavy wooden desk, his single visible eye fixed on the three kneeling figures before him.

The ROOT agents - one each from the Aburame, Nara, and Akimichi clans - remained perfectly still, their blank masks betraying no emotion. Despite their recent defeat, their postures were rigid, a testament to their unwavering loyalty and conditioning.

"Report." Danzo commanded, his voice a low, authoritative rumble that seemed to make the very air heavy with tension.

The Aburame spoke first, his voice monotone and devoid of any hint of the fear or shame a normal shinobi might feel after a failed mission. "Target Monkey D. Garp demonstrated combat abilities far exceeding initial estimates. Our combined assault proved ineffective."

The Nara continued seamlessly, as if they were one entity rather than three separate individuals. "Subject displayed physical strength capable of nullifying clan techniques. Kagemane no Jutsu was rendered useless by the target's raw power."

"Nikudan Sensha was halted with a single hand," the Akimichi added, his voice equally flat despite the extraordinary nature of what he was describing. "Target's speed and reflexes surpass those of all jōnin-level shinobim and that was without taking the fight serious."

Danzo's expression remained impassive, but his mind was racing, analyzing every piece of information. "Elaborate on his fighting style," he ordered.

"The target utilized no recognizable ninjutsu or genjutsu," the Aburame reported. "However, he demonstrated an unknown ability that rendered my kikaichū ineffective."

"Most notably." the Akimichi concluded, "The target emitted a wave of... presence, for lack of a better term. It overwhelmed our senses and rendered us unconscious."

Danzo leaned back slightly, his hand absently tracing the bandages covering his right eye. The picture these reports painted was troubling. A warrior of immense physical prowess, with abilities unknown to the shinobi world, now resided in Amegakure. This Garp could upset the delicate balance of power Danzo had worked so hard to maintain.

"And his connection to Hanzo?" Danzo questioned, his tone sharp.

"Unclear," the Aburame responded. "However, the target has taken custody of three orphans.

Danzo rose from his seat, his movements deliberate and powerful despite his age. He walked to a wall covered in maps and intelligence reports, his single eye scanning the information with frightening intensity.

"You are dismissed," he said to the agents, not bothering to look back at them. "Report to reconditioning and await further orders."

The three ROOT members vanished without a sound, leaving Danzo alone with his thoughts.

He considered the situation carefully. This Garp was clearly a wild card, a piece on the board that didn't follow the usual rules. Such elements were dangerous... but also potentially useful.

Danzo's mind, honed by decades of political maneuvering and covert operations, began to formulate plans. Perhaps this outsider could be manipulated, used to destabilize Amegakure from within. Or, if he proved amenable, he could be a powerful ally in Danzo's quest to strengthen Konoha.

And if he proved to be a threat... well, even the mightiest tree could fall if the roots were poisoned properly.

A thin, cold smile spread across Danzo's face. He reached out with his good arm, tracing a line on the map from Konoha to Amegakure.

"Monkey D. Garp," he murmured, the name rolling off his tongue like a challenge. "Let's see what role you'll play in the grand scheme of things."

Danzo's resolve hardened. Whether as an ally or an enemy, this Garp would serve Konoha's interests. And if he refused... well, even the mightiest warriors had weaknesses. Those three orphans, for instance, could prove to be very useful leverage.

Danzo returned to his desk, already drafting orders for his next moves. The shinobi world was changing, and he would ensure that Konoha emerged stronger for it, no matter the cost