Punk Hazard—once a top-secret Navy research facility—had long been abandoned after a catastrophic accident. But Caesar Clown had snuck back in, reclaiming the island and transforming it into his own twisted laboratory.

There, he didn't just conduct all kinds of forbidden human experiments—he was also working hand-in-hand with Doflamingo, developing a mysterious substance known as SAD.

It was the key ingredient for mass-producing artificial Devil Fruits.

And more than that—it was the foundation of Doflamingo's major business deal with one of the Four Emperors: Kaido.

Chiyu, Franky, Blade, and Box landed on Punk Hazard, and right away, they felt it—a thick, suffocating dread hanging in the air. The sky was a dull, stormy gray, and the entire island reeked of something ominous.

The squad wasted no time prepping for a fight.

Before long, a mob of grotesque, half-human monstrosities showed up. They looked like bio-engineered freaks—mutants that reminded them of the monsters from Thriller Bark.

The moment they saw Chiyu, they charged without hesitation.

Franky cracked his knuckles and grinned.

"Let's rumble."

"Franky Weapon—Left Punch!"

"Franky Power—Right Punch!"

Blade unleashed his Elephant Blade with a booming swing.

"Elephant Slash!"

Box shifted straight into his Giraffe Zoan form, muscles bulging, speed ramping up. He went full quad-mode, fighting with all four limbs like a beast.

He unleashed Navy Six-Style moves—Finger Pistol and Tempest Kick—supercharged by his Devil Fruit. The results were terrifying.

Even though the island was crawling with enemies, they were cannon fodder—no match for fighters like these.

"Wait—who is that guy?!"

"Why does he look so damn familiar?!"

"Hold on… That's—Uchiha Chiyu?!"

Panic exploded across the battlefield.

These monsters knew the name.

Uchiha Chiyu. A name now spoken with the same fear as Whitebeard, Edward Newgate.

But unlike Whitebeard, Chiyu didn't wait for people to come to him.

If you crossed his path and you were a pirate or a villain… you were already dead.

The enemy scattered like rats.

"Running? Not so fast!"

Franky and the others already knew the score. Caesar's lackeys were scum—Chiyu had told them about the twisted experiments happening here. There'd be no mercy.

Chiyu raised one hand and whispered:

"Judgment of the Gods."

Lightning rained down like divine punishment, ripping through the land, erasing monsters, purging the poisonous fog that clung to the island.

Even the terrain trembled.

"Whoa… his power's still growing?"

"One swing, and the place turns into Thunder Island..."

Their rampage didn't go unnoticed.

From the center of the island, a massive figure burst from the lab—his entire body was white smoke, his face twisted into a ridiculous grin, his voice shrill.

"Who the hell's tearing up my island?!"

Caesar Clown.

Two others followed closely behind.

One was the newly appointed Warlord: Trafalgar Law.

The other—a top officer of Doflamingo's: Monet the Snow Woman.

The moment they laid eyes on Chiyu, all three froze.

"No way… You're—"

"Uchiha Chiyu?!" Law muttered, his brow twitching.

"The guy the Young Master ordered us to kill?!" Monet whispered, her face going pale.

Caesar's jaw dropped. Of course he'd heard of Chiyu.

"You're a wanted man, too! Why are you here?! I didn't mess with you!"

Chiyu's voice was cold.

"You did."

He lifted his hand—and BOOM, a thunderbolt slammed straight into Caesar.

Law and Monet instinctively jumped back, dodging the blast.

Caesar took the full hit—fried from the outside in. But somehow, he survived—turning into gas just in time to avoid total vaporization. Still, the hit left him wrecked and gasping.

"Damn it… What the hell do you want, Chiyu?! Don't you know who I'm working for?!"

"I'm not just helping Doffy anymore. I'm working for two Emperors!"

That made Chiyu pause.

SAD was for SMILE production—that meant Kaido was involved. And the other Emperor?

Big Mom, no doubt.

So Caesar really was the guy running those experiments to enlarge children.

Chiyu's eyes darkened.

"So the kids… they're already here?"

Caesar flinched.

"H‑How do you know—"

"Release them," Chiyu said, flat and cold.

"You think you can order me around?! I'm Caesar Clown! A genius scientist! Backed by two Warlords, and two Emperors!"

"Three," Chiyu replied.

"What?!"

"Two."

"Y‑You can't scare me—!"

"One."

"You kill me, and those kids die with me!"

Chiyu didn't even blink. He vanished—instantly appearing behind Caesar.

Shusui flashed.

Caesar didn't react in time. He was seconds away from being sliced in half—

"ROOM!"

Law shouted, summoning a massive dome of energy. In an instant, Caesar was teleported away.

Chiyu's blade hit air. A rare miss.

He turned to Law, calm but deadly.

"So you've chosen death too?"

"He's still useful to me," Law replied sharply.

"Kill him after I'm done with him."

In truth, Law's real goal had nothing to do with Caesar or SAD.

He wanted revenge. For Corazon.

To kill Doflamingo.

To get close, Law had given Caesar his own heart. As leverage, he also stole Monet's. Mutual blackmail. Perfect balance.

If Caesar died now, Law might drop dead, too.

Chiyu didn't care.

He raised a finger—lightning roared out like a javelin, tearing the air apart.

Law panicked, activating ROOM again and teleporting just in time—leaving Caesar exposed once more.

Caesar gasped.

"Screw you, Chiyu!"

"If I die—then no one's walking out of here!"

"LAND OF DEATH!!"

Caesar's trump card.

Purple poison gas burst from every direction, swallowing the island whole.

Any living thing it touched—instantly dead.

Animals. Plants. Even his own men.

He didn't care.

They screamed. They begged.

Caesar just laughed like a lunatic.

His own followers finally saw what he really was—a monster. But it was far too late.

The gas turned everything it touched into stone-white corpses—petrified in agony.

Even Law and Monet couldn't hide their disgust.

This was hell.

But Caesar? Still laughing.

Law clenched his fists. Then turned.

"Uchiha Chiyu."

"Screw it. Just kill him."

"I'm going to find my heart—and save those kids."

Chiyu nodded, still facing Caesar.

"Franky. Blade. Box. Go with him. Make sure those kids get out safely."

"Yes, sir!"

Monet wasn't having it.

"You're not ruining the Young Master's plans!"

She flew after them, using her Snow-Snow Fruit to sprout massive wings, ready to intercept.

That left only two people behind.

Uchiha Chiyu.

Caesar Clown.

Caesar's body had transformed—pure purple gas, towering and monstrous. His chest glowed with two kanji: 死国.

This was his final form.

A massive slime-like creature slithered up beside him, shaped like a six-legged salamander.

It was pure poison, fused with a Zoan-type Salamander Devil Fruit—the first time a non-living thing had eaten a Devil Fruit.

Caesar cackled.

"This is my turf, Chiyu! You don't stand a chance here!"

"I don't care how strong you are—you still need to breathe!"

"One breath of my gas and you're DEAD!"

"Don't underestimate the Gas-Gas Fruit!"

"Gastanet!!!"