One Piece: I will become stronger by checking in

"You're not bad either, kid!" Garp smirked at Kai, his voice calm but laced with respect.

Kai met Garp's gaze with a slight smile, choosing not to reply. Though their clash hadn't lasted long, Kai could sense the overwhelming power in Garp's Armament Haki—it was leagues above his own.

Top-tier, Kai thought to himself. No wonder he's known as a Marine legend.

He couldn't help but admire Garp's strength. But as much as he respected it, Kai's confidence didn't waver. "With that level of power, if you weren't busy chasing the so-called 'Deserter King,' there wouldn't be many in this world who could take you on," Kai remarked, his tone teasing.

Garp blinked, confused by the comment. "What Deserter King? And why would I save him?"

"You'll find out soon enough," Kai replied with a smirk, cutting off Garp's train of thought.

Without giving Garp time to process, Kai launched himself forward, his speed leaving shockwaves in the air. The black iron club in his hand swung with devastating force, aiming directly for Garp's head.

But Garp didn't back down. With a grin, he charged in with his trademark iron fist, his Armament Haki gleaming. Their weapons collided, creating a shockwave that shattered the air around them and sent tremors through the battlefield.

As the fight raged on, Garp began to feel the strain. Kai's relentless attacks grew fiercer with every swing. Damn it… this kid's getting stronger as we go! Garp thought. While his years of experience kept him steady, age had undeniably dulled his edge.

Kai, on the other hand, felt unstoppable. He wasn't sure if Garp had the legendary Conqueror's Haki, but if he did, he hadn't used it yet. Either way, Kai didn't care. Garp's brute strength and mastery of Armament and Observation Haki alone made him a formidable foe.

But Kai had something Garp didn't—a monstrous physical advantage, his demonized form, and his devastating techniques. Coupled with his clones, he was a force to be reckoned with.

"Not bad, old man," Kai taunted mid-battle, his strikes becoming heavier, faster, and harder to block. "But let's see if you can handle this!"

Meanwhile, on the battlefield, the CP0 and CP9 agents were in shambles. Their breaths came in ragged gasps, and fear flickered in their eyes as they watched the chaos unfold.

With a wicked grin, Kai's clone turned his attention to the group. "The Laws of Heaven and Earth!"

In an instant, his body grew to a colossal size, towering over the battlefield. With a single swing of his now-massive iron club, he sent a devastating blow toward the CP0 agents.

"Brace yourselves!" shouted one of the leaders, rallying their comrades to counter. But their combined attacks were pitiful against the overwhelming power of Kai's strike. In mere moments, the CP0 and CP9 were crushed and sent flying into the sea.

Kai shook his head in disdain. "What a waste of time," he muttered. The agents were no match for him or his clones. Even someone like Kaku wasn't worth the effort—it was laughable.

Elsewhere, Aokiji was locked in his own battle against one of Kai's clones. The surrounding sea was frozen solid, and the icy air made the battlefield feel like a wasteland.

Aokiji watched his opponent carefully, frustration etched on his face. He had known Kai had potential when they last fought, but this was something else entirely.

This is ridiculous, he thought. In just a few weeks, this brat has gone from being a decent opponent to someone who can overpower me—and this isn't even his real body!

His gaze darted across the battlefield. Everywhere he looked, Kai had the upper hand. It wasn't just his overwhelming strength but the sheer dominance of his clones.

If he keeps this up… even the Four Emperors won't compare to him, Aokiji realized grimly.

Suddenly, Kai's two clones joined forces with his main body. Standing side by side, they raised their clubs in unison. Aokiji's heart sank as he recognized the stance.

"No way…" he muttered before springing into action. "Garp! Get out of there!" he shouted, racing toward the Marine hero.

But Garp was locked in place, his instincts screaming at him. He could feel the immense power radiating from Kai's next move—it was too late to dodge.

Kai's voice boomed, laced with raw power. "Hakai!"

The two clubs slammed together, unleashing a massive, focused shockwave. The attack ripped through the battlefield with incredible speed, obliterating everything in its path.

Garp clenched his fists, his Armament Haki surging.

He braced himself, ready to meet the devastating force head-on.