When does Luffy fight Katakuri?

Luffy engages in a battle with Katakuri to protect his friends but despite his efforts, he proves to be no match for Katakuri. However, Katakuri states that Luffy can become a great threat to Big Mom and the Big Mom Pirates in the future, so he will eliminate him right now and make Mirro-World Luffy's grave.

As Luffy is struggling to beat Katakuri, his subordinates claim that Luffy cannot dream of ever defeating him, as he is worth more than a billion berries and is thus leagues above Luffy. Despite all this, Luffy is determined to defeat him and launches a series of attacks but Katakuri dodges them all with his advanced Observation Haki which gives him the ability to see a glimpse of the future. After a while, Luffy starts to pound Katakuri quickly, but instead of dodging, Katakuri makes mochi tendrils from his back into fists, and he perfectly parries all of Luffy's blows with the mochi fists.

Katakuri goes as far as to beat Luffy senselessly and crashes him into a wall, which his subordinates claim to be too brutal. Now dragged into a corner, Luffy activates Gear 2 to beat him with speed, but Katakuri matches his speed and even surpassed him and kicked Luffy into the wall. Then, with his advanced Observation Haki, Katakuri states that Luffy will use Gear 3 now.

The Thousand Sunny, meanwhile, crashes back into the water far from Whole Cake Island, thanks to Coup de Burst. After a brief search, the team concludes that Luffy must have gone to the Mirro-World with Katakuri. Brook and Chopper then question where Pedro is, and Nami tells them of Pedro's sacrifice as it begins to rain. Brook, Chopper, Nami and Carrot start to cry and become emotional, but Jinbe instructs them not to cry and rather stay focused as they are not out of harm's way.

Brook is upset by this and accuses Jinbe of being cold. Jinbe explains that Pedro was preparing to sacrifice himself and that it was his sacrifice that freed them from the Big Mom Pirates' attack on Whole Cake Island. Now, if they don't focus and get caught, then his sacrifice would mean nothing. Brook apologizes to Jimbe for his cruel words and then all of them get in action and get to their stations.

Carrot soon notices that they are being pursued by the Big Mom pirates who are right behind them and Big Mom is walking on a candy sea slug, accompanying her fleet. They soon realize that Perospero is the only one who can create the candy sea slug and is still alive. Sanji learns that Lola is a skilled chocolatier as he, Chiffon, Pudding, and Nitro ride Rabiyan toward Cacao Island.

Chiffon tells that Lola was the Minister of Chocolate who ruled over Cacao Island before fleeing, and the job has been vacant ever since because the best candidate, Pudding, refuses to take Lola's place. Pudding states that she does not want to become the Minister of Chocolate because in her perspective, Lola is the only worthy candidate to fulfill that position and she is waiting for her return. Pudding is currently curled up in Rabiyan's rolled-up front, refusing to come out since she does not want to be seen with Sanji in her wedding gown.

Pound, Chiffon and Lola's father, is departing in the sea below when he notices Chiffon standing above him. As her crew approaches Cacao Island, he tries to shout out to his daughter but is unsuccessful get their attention.

1. The battle with Katakuri proves to be no match for Luffy.
2. It is revealed that Charlotte Perospero survived the blast and is alive but lost his right arm in the explosion.

Luffy fights Katakuri in episode 851, titled, 'The Man with a Billion Bounty - The Strongest Sweet Commander, Katakuri. Luffy and Katakuri engage in a violent battle in the Mirro-World. The crew on the Thousand Sunny mourn Pedro's selflessness after leaving Whole Cake Island, but Jinbe suggests them to keep their attention on escaping Totto Land. Soon, Big Mom and a small fleet eventually find and pursue them. On the other hand, Sanji, Pudding, and Chiffon are approaching Cacao Island in the meantime.