Kahn hadn't anticipated that his actions would cause such a chain reaction, eventually leading to Luffy meeting Momonosuke. Now, it's uncertain if the stunned Luffy will still decide to help Momonosuke reclaim Wano.
If Luffy helps Momonosuke take back Wano, it essentially means Kahn has taken Kaido's place as the first Emperor Luffy will challenge head-on in the New World. Why "first" and not "second"? Well, it's simple: in the original story, Luffy's encounters with Charlotte Linlin were more to retrieve Sanji than to defeat her as a primary target. Kaido, however, was Luffy's first direct challenge, and no matter the number of setbacks, Kaido was the one he was determined to beat.
Because of this, Luffy's strength skyrocketed as he clashed with monsters of the New World, reaching the peak of Yonko-level power and becoming the youngest Emperor. If Kahn indeed steps into Kaido's role, he'll become the target that Destiny's Child (Luffy) must defeat.
Will this battle push Luffy to master the highest level of Armament Haki, Conqueror's infusion, and ultimately reach Gear 5 or Nika's awakening? Pondering this, Kahn sneered, dismissing the thought of Destiny's Child.
He hoped Luffy wouldn't foolishly challenge him for the sake of a near-stranger like Momonosuke. But if he did, Kahn had no qualms about ending this era of unrest before it even fully began. Eight hundred years of waiting could simply roll into a new cycle.
Kahn wasn't too concerned about Destiny's Child coming after him. Even the protagonist's aura has limits. In the original, Luffy had the help of Eustass Kid and Trafalgar Law to occupy Charlotte Linlin, plus the support of Marco, a capable ally, which set up his chance to confront Kaido one-on-one. Even then, it took Luffy losing twice and finally achieving Nika's form after extensive battles to win.
But facing the "Cross Guild" and Kahn—who is well aware of Nika's abilities—would be an entirely different challenge. Unless every member of the Straw Hat Pirates reaches Emperor-level power, they will struggle against the Cross Guild's resources. Kahn himself wouldn't even need to step in; Boa Hancock could lead the Perfect Legion and Seraphim to wipe out the alliance of the Straw Hats, the Mink Tribe, and the remaining Nine Red Scabbards.
This is on a different level than any previous war Luffy has faced. Even if he achieves Nika's form, he might still struggle against the current Hancock. While his rubber powers give him some immunity to lightning and fire, this protection has its limits. Just as Akainu's magma left a cross-shaped scar on his chest in the original, Hancock's current strength as a Yonko-level fighter poses a threat even to Nika Luffy.
With her incredible speed, Hancock could evade even Kahn's grip. And if Kahn tried to restrain her with telekinetic powers, she could teleport to break free, effortlessly escaping his grasp.
Hancock's mastery of the Thunder Fruit has reached an impressive level, rivalling that of an Admiral's development of their Devil Fruits. When two Devil Fruits are similarly advanced, the winner depends on whose elemental powers are superior and who holds the greater advantage in battle.
On top of her Devil Fruit skills, Hancock's Haki abilities are extraordinary. By 1515 of the Sea Circle Calendar, Hancock had already achieved mastery over the most advanced uses of Conqueror's Haki. She could perform external and internal destruction through Armament Haki, predict the future with Observation Haki, and infuse Conqueror's Haki into her attacks—abilities she'd honed seven years prior.
Yet, due to the overwhelming power of the Cross Guild and the defeat of the Beasts Pirates, no other force, not even those at the Yonko level, dared to challenge Hancock or the Guild. Thus, the world's view of her abilities remains rooted in the past, unaware of her growth. Hancock has risen to a level on par with legends like Benn Beckman, the right-hand man of Red-Haired Shanks, capable of rivalling her captain or trailing only slightly behind.
Meanwhile, Kahn has turned his focus away from Luffy, who, much like the original story, continues his journey after defeating Caesar, with Momonosuke—still recovering from an experiment—and his protector, Kin'emon. Their journey to find Raizo leads them, by either chance or fate, to Zou, the land atop the ancient elephant, Zunesha.
For the Straw Hat Pirates, this first encounter with Zunesha, a massive prehistoric creature, was a revelation, reshaping their sense of scale. Even the enormous Noah and the Sea Kings of Fish-Man Island seemed minuscule by comparison.
Unlike in the original story, where Zou suffered devastation from Jack of the Beasts Pirates, this time, Kaido's forces have left Zou undisturbed. As a result, the Mink Tribe had no need to hide or lie to protect Raizo from pirate attacks, allowing Kin'emon and the crew to reunite with Raizo and obtain their first copy of the Poneglyph.
Kahn, being aware of the world's secrets, knows there's a Road Poneglyph on Zou's island, on Zunesha's back. However, Kahn has no interest in finding Raftel, the final island, and therefore hasn't pursued this Poneglyph. Besides, he already possesses a Road Poneglyph—a prize from his battle with Kaido.
As for why Kaido had a Road Poneglyph, it originates from Wano. During Roger's era, the four Poneglyphs were hidden in Totto Land under Charlotte Linlin's rule, on Zou, in Wano, and finally on Fish-Man Island, next to Joy Boy's apology.
After Roger's era, however, the Fish-Man Island Poneglyph disappeared, removed by unknown hands. Kaido was cast out from Onigashima by Kahn without obtaining it. Now, if Luffy wishes to become the Pirate King, he'll need to confront Kahn in Wano and obtain a copy of the Poneglyph from him. Kahn holds the final key to reaching Raftel and unlocking the last piece of the puzzle.
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