Katakuri was naturally gifted with an exceptional level of Observation Haki, even to the point where he could briefly foresee the future.
So, during battle, he could 'see' a few seconds ahead.
After dodging numerous slashes, he immediately launched his spiraling thrust toward Nicholas. The mochi spiral, trailing white vapor, shot toward Nicholas like a missile.
Seeing this, Nicholas's eyes flashed red. He swung his sword, slicing the spiraling mochi missile in half.
Almost instantly, as his sword cleaved through the spiral mochi missile, a mass of sticky mochi erupted from within, aiming to engulf Nicholas.
At that moment, Katakuri, armed with the Trident imbued with Haki, lunged directly at Nicholas.
Simultaneously, several donuts appeared behind him, from which large, Haki-enhanced mochi arms extended, attacking Nicholas from all directions.
"You've let your guard down, Nicholas! Mochi Gunkan!" Katakuri shouted.
All his previous attacks were a diversion for this moment.
Because he had 'seen' it: against Nicholas, his usual attacks were futile.
What was happening now was the only scenario he foresaw where he might defeat Nicholas.
Nicholas, observing the seemingly airtight attack, said calmly, "Let my guard down? That's impossible."
Katakuri heard Nicholas sigh and say, "Sometimes, the gap in strength can really create an illusion."
Nicholas's words stunned Katakuri. However, his resolve hardened, and his actions didn't pause for a moment.
"Die!"
First, the sticky mochi hidden in the Mochi Spiral Thrust covered Nicholas.
Then, the Haki-covered mochi arms, constructed from mochi, followed and struck Nicholas. The massive mochi arms quickly buried Nicholas's figure, obscuring the scene.
Despite the successful execution of his plan, Katakuri showed no signs of triumph. He vibrated his arms, and his Trident moved like a fierce dragon, piercing through the mochi that had parted to the sides.
"Not bad, Katakuri..." Before the Trident could pierce deep enough, Nicholas's calm voice sounded from within.
Katakuri felt a sudden jolt in his hands. The Trident could no longer advance.
He could clearly sense that the Trident was being held back by an invisible force, which continued to expand outward.
Finally, as a terrifying force surged through the Trident, Katakuri withdrew it and leaped backward. Amidst the rain of scattered mochi, Nicholas emerged unscathed.
In his outstretched hand, arcs of electricity danced continuously.
Was it a power?
Seeing Nicholas, completely unharmed, and the electric arcs jumping from his hand, Katakuri instinctively narrowed his eyes.
Nicholas looked at him and smiled, "Are you confused? You should've 'seen' it, but what's happening now seems different from what you saw."
When it came to future-sight through Observation Haki, no one understood it better than Nicholas.
"Just a little off, huh?"
"Just a little off?"
As soon as this thought occurred to Katakuri, he heard Nicholas speak. Instantly, he looked at Nicholas in disbelief.
"Mochi Cannon!"
Without hesitation, Katakuri launched another attack.
Bam!
A powerful punch hit Nicholas's body with a heavy thud.
However, Nicholas remained unmoved by the punch. A closer look revealed that there seemed to be an invisible barrier separating Katakuri's attack from Nicholas's body.
This invisible barrier stood around Nicholas, blocking Katakuri's assault.
"Mochi Clap!"
Two mochi circles quickly formed on either side of Katakuri's body, from which two large, Haki-covered mochi hands emerged, slamming toward Nicholas in the middle.
"Doughnut Mochi!"
Just as those hands clapped down, Katakuri created several large donuts above, from which countless Haki-infused spikes extended, all aimed at Nicholas.
Clang, clang, clang!
The spikes struck Nicholas's barrier, producing loud sounds.
When the last spike vanished, Katakuri chose to stop.
He realized he couldn't do anything to Nicholas. Whatever this invisible defense was, he couldn't break through it.
Without a way to penetrate Nicholas's defense, no matter how much he foresaw or attacked, he wouldn't be able to trouble Nicholas.
Nicholas saw the Doughnut Mochi attacks disappear in mid-air and looked at Katakuri, "Giving up?"
"Not yet!"
Katakuri gritted his teeth, spreading his arms wide. A mass of mochi circles filled the space above Nicholas and Katakuri.
Inside the circles, numerous Haki-covered mochi fists aimed at Nicholas below.
"A futile struggle."
Nicholas shook his head, a slight smile on his lips. "You've been attacking for so long; now it's my turn."
The next moment, Nicholas's figure vanished.
Katakuri instinctively used his Observation Haki to look into the 'future.' As long as he could 'see' what would happen a few seconds ahead, he could figure out a way to block Nicholas's attack.
But until Nicholas appeared behind him, he didn't 'see' anything.
If Nicholas hadn't had his sword against Katakuri's neck, he'd think he was dreaming.
His Observation Haki, capable of briefly foreseeing the future, failed against Nicholas.
Katakuri was left in a daze.
He didn't even notice when Nicholas and the sword at his neck, which had turned into lightning, disappeared.
"Nicholas, you overdid it this time; that kid's completely lost it," Kizaru laughed, seeing the blank expression on Katakuri's face.
"He's not that easy to break."
"What was that?" Katakuri suddenly asked.
Nicholas was slightly stunned but quickly realized what Katakuri was referring to.
Smiling, he said, "That was Bio electric manipulation to form a barrier, the world's strongest weapon!"
Hearing Nicholas's answer, Katakuri murmured, "The world's strongest weapon is... a Barrier?"
[AN – For anyone wondering, isn't bio electricity weak compared to natural lightning? The answer is yes, but after awakening logia fruit, the world becomes one's body part. Like a Domain its easier to control things inside a domain compared to the outside.]
Ignoring another person stunned by the version, Nicholas continued discussing the upcoming plan with Kizaru.
...
With Nicholas showing his strength, Katakuri understood that the Charlotte family had no option but to accept Nicholas's terms.
So, he accepted the position of Commander-in-Chief of the New World Anti-Pirate Task Force.
He planned to return to Totto Land and lead the Charlotte family to start targeting the pirates of the New World.