Three days later, at the Marineford training grounds.

The scorching sun hung high, and the air was filled with a burning sensation.

In the center of the training grounds, Libo and Tesoro were blindfolded with black eye masks, their figures clumsily dodging left and right.

Under their feet was a specially designed vibrating grid; every step they took would trigger a faint tremor, disrupting their balance.

"Left! No... right!" Libo's furry ears perked up, and fine beads of sweat trickled down her forehead.

Her carrot hair ornament swayed slightly with her rapid breathing as she tried to catch the subtle sounds in the air through her hearing.

"Bang!" Just then, a pale particle ray grazed her shoulder, exploding into a tiny pit on the ground.

"Almost!" Libo, who had barely dodged, exclaimed, touching her small chest.

But then another ray shot from the completely opposite direction, accurately hitting her knee.

"Ah!" She stumbled, almost falling, but gritted her teeth, stabilized herself, and continued to jump on the grid.

Not far away, under the awning, Gern lay lazily on a lounge chair, holding a chilled watermelon juice in one hand and slowly taking a sip.

His other hand was casually raised, low-energy vibrating particles condensed at his fingertips, and with a light flick, another ray shot out.

Compared to high-energy particles, the destructive power of the vibration produced by low-energy particles was almost controlled by Gern to be similar to being flicked by a small pebble.

After all, after his Devil Fruit awakening, Gern found that his control over vibrations was even more effortless.

Especially compared to the super-enhancement of the Animal Type's physical body and the transformation and assimilation of the Paramecia Type, the awakening of the Nature Type mostly manifested in everyday control.

Of course, 【Domain Expansion】 was the true form of the awakening mode, but unless it was a life-or-death situation, it was generally not used.

"Tesoro, your movements are too stiff."

Gern took a big gulp of juice, sighed, and shook his head, "Observation Haki isn't about seeing; it's about sensing.

When Bullet blasted you away with one punch, if you could have predicted it by half a second, you wouldn't have been lying there for so long."

"Me? Predict Bullet's movements by half a second?!" Tesoro's mouth twitched.

"Vice Admiral Gern, when you were trained by Vice Admiral Garp..." While speaking, he barely dodged a ray and asked, panting, "Was it also this intense?"

"Huh? This intense?" Gern scoffed, put down his watermelon juice, and sat upright, "Vice Admiral Garp was much harsher than this."

As he spoke, Gern's eyes blurred slightly, as if recalling the time when he was subjected to hellish special training by Zephyr and Garp.

Especially Garp's cannonballs, imbued with Haki; each blow was enough to shatter mountains.

And it was under pure Haki suppression that he painstakingly honed his Observation Haki instincts.

"Back then, no one reminded me where to dodge; Vice Admiral Garp was trying to kill me!

You guys are still lucky! At least I didn't tie you up with chains and throw you into the sea when I made you practice Armament Haki."

"Th-throw into the sea? And tied with chains...?"

Libo and Tesoro, both Devil Fruit users, recalled Garp's usual easygoing demeanor and instinctively swallowed.

"Vice Admiral Garp was a formidable character in his youth!"

"No, no, Gern, who survived, is even more of a figure."

"So..." Gern shrugged, particles condensed at his fingertips again, "Stop complaining, continue!"

"Whoosh!" Another ray shot out, this time heading straight for Tesoro's chest.

Tesoro sharply turned sideways, the ray grazing his clothes, but the next second, another ray from a tricky angle directly hit his back.

"Ugh!" He grunted, knelt on one knee, and gritted his teeth, "Damn it, how is this possible to dodge?!"

"Why not possible?" Gern raised an eyebrow, "The essence of Observation Haki is 'listening to the voice of all things.'

Not just the enemy's attacks, but also the flow of air, the vibration of the ground, and even..."

He suddenly paused, the vibrating particles at his fingertips suddenly intensified, and a ray ten times faster than before shot out!

"The opponent's killing intent!"

Libo and Tesoro's hair stood on end simultaneously, instinctively diving to both sides.

"Boom!" The ray exploded at their original standing position, and the air current stirred up the surrounding dust.

"Not bad, finally some progress." Gern nodded in satisfaction, stood up, and stretched.

"That's enough for today."

Libo pulled off her eye mask and collapsed to the ground, panting heavily, her rabbit ears drooping weakly: "Gern, isn't that too strict...?"

"Strict?" Gern walked up to her, squatted down, and lightly flicked her forehead.

"If you can't even withstand this level of training, how will you face the monsters of the New World in the future?

Those guys won't go easy on you."

Tesoro silently took off his eye mask, a hint of unwillingness flashing in his pupils.

"Vice Admiral Gern, can we... really become that strong?"

Gern looked at him and suddenly smiled, "Of course."

"Because the coming era... will only be more brutal than now."

"Although I don't require you to reach the Admiral level, you will need the strength to deal with that group of First Mates later..."

Gern did not say the last sentence aloud, only mused it in his heart.

Thinking of this, Gern had just gotten up, ready to let the two rest, when suddenly, he paused.

The air temperature plummeted, and his vibration sense detected water molecules in the air turning into ice flowers.

At the same time, a wisp of cold air silently brushed past the back of his neck, and almost at the same instant,

A fist-sized ice ball tore through the air, heading straight for the back of his heart at nearly the speed of sound!

"Heh." Gern's mouth curved slightly, he didn't even turn his head, just casually raised his left hand backward.

"Bang!!!" The ice ball exploded in his palm, and the terrifying impact turned into a visible air current, causing the ground beneath his feet to "crack" and collapse into spiderweb-like cracks.

Cold air permeated, and ice crystals spread along his arm, but they were shattered by his Armament Haki-hardened muscles the instant they touched his skin, falling off like dust.

Gern slowly withdrew his hand, flicked off the remaining ice chips on his wrist, and then turned around, looking at the training ground entrance with a half-smile.

"Sneak attack?" He raised an eyebrow, "Kuzan, when did you learn such a petty trick?"

From the shadows, a tall figure slowly walked out.

Kuzan, hands in his pockets, smiled slightly, and the white mist he exhaled condensed into frost in the air.

"Oh my... I've been discovered." He scratched his head, his tone still lazy, but his eyes were unusually sharp.

"However, to be able to take my 'attack' so easily, it really can only be you... Gern."

Libo and Tesoro, who were slumped on the ground, their pupils constricted.

If that last attack had been aimed at them, they probably wouldn't even have had time to react!

Gern, however, just chuckled softly, his fingertips vibrating slightly, dispelling the last trace of cold air.

"Hahaha." He looked directly at Kuzan, smiling, "It seems Fleet Admiral Kong has already delivered the World Government's 'notice' to you, huh!"

"Kuzan."