Compared to her three sons, Charlotte Linlin progressed much faster in practicing the "King's Fist."
In less than a month, this born conqueror had mastered "Eight Apples," something even the founder of the King's Fist—the Pudding Royal Family's ancient ancestor—had failed to achieve. It allowed her to store an additional amount of Armament Haki equivalent to three times her maximum Haki capacity, and this was not even her limit.
It was simply that Charlotte Linlin herself was already too strong. Even the beginner-level King's Fist was basically enough for her.
Training it further would only extend its effective range and make it harder for enemies to evade. (If the power was sufficient, there was no need to rotate it, or the rotation speed could be slowed to increase the striking surface.) It was not completely useless, but at most it was merely icing on the cake.
Furthermore, Charlotte Linlin's Armament Haki had already reached the highest realm, as natural as moving her own limbs. (What she lacked compared to Garp was knowing how to use it to hit people the hardest, but purely in terms of Armament Haki itself, Charlotte Linlin—who had turned it into bodily instinct in childhood—was unmatched.) Training in the King's Fist brought her no additional benefit.
So after reaching the point where she could no longer improve rapidly, she could not be bothered to continue. Instead, she spent more time training Body Techniques, including sparring with Katakuri.
As a result, Charlotte Katakuri had much less time to practice the King's Fist as well. But he had only trained it in the first place because it benefited his Armament Haki cultivation. No matter how effective punching practice was, it could not compare with real combat against a stronger opponent. Now that his mother was willing to spar