Warning: spoilers for One Piece chapter #1035
In One Piece's latest chapter, Zoro, the swordsman of the Straw Hat Pirates, has just unlocked a new level of power during his fight against King the Wildfire. Putting together the techniques from his Santōryū (Three Swords Style), the power of the legendary sword Enma, and his newfound ability to channel Haoshoku Haki (Conqueror's Haki) in his attacks, Zoro unleashed a powerful strike that cut through King's nigh-impenetrable defenses.
The fight between the Straw Hats and Kaidou's Beasts Pirates is the climax of the Wano Arc. Captain Luffy and his crew faced many powerful opponents during their adventures, but this time they are up against one of the Four Emperors, Kaidou, who is also considered "the world's strongest creature". The Straw Hats had to improve fast and reach the next step of their potential, which for Luffy and Zoro consisted in mastering Conqueror's Haki, a very rare form of Haki (the mysterious spiritual energy that appears throughout the series) that is owned only by individuals with the potential to be great rulers. Until recently, Conqueror's Haki was shown only as being able to intimidate and incapacitate others, but the Wano Arc has revealed that a handful of individuals can infuse their bodies and weapons with Haoshoku, augmenting the power of their attacks.
While Luffy had to quickly master this new ability to go one-on-one against Kaidou, Zoro was shown having trouble keeping up with his selected opponent, King. Due to his Lunarian heritage, King is resilient to all attacks. Besides that, Zoro was also struggling to master his new sword Enma, who belonged to legendary Wano hero Kozuki Oden, but has the dangerous characteristic of constantly absorbing his holder's Haki. During the fight, Zoro found the resolve he needed to overcome these obstacles. He mastered Enma by letting her absorb as much energy as she wants, and unleashed his Conqueror's Haki consciously for the first time, imbuing his swords with it and finally cutting King and revealing his face. The duel was not over, however. King's natural endurance and his ability to produce and manipulate flames are highly enhanced by the powers of his Devil Fruit, the Ryu Ryu no Mi, Model: Pteranodon. With both fighters exhausted, it was time for one final attack to decide the outcome of their clash.
King unleashed his "Imperial Guardian Flaming Dragon", a dragon-shaped burst of flames. Zoro countered with a finishing attack of his own that ties together every weapon in his arsenal: "Underworld's King Three Swords Style: 130 Emotions, Flying Dragon Hell Blaze." "Underworld's King" is the meaning of the name of the sword Enma, a legendary guardian deity of the underworld in Buddhism and Japanese mythology. The Three Swords Style is the one Zoro developed personally, to carry on his childhood friend Kuina's dream of becoming the strongest swordsman in the world. In that style, the "Flying Dragon Blaze" (Hiryū: Kaen) is an attack that Zoro previously performed using only one sword, and was powerful enough to worry even Kaidou. Now, he has used it with the Three Swords Style, and imbued it with Conqueror's Haki, resulting in a strike so powerful that it cut through King's flame dragon and then through King himself, severing his sword and one of his wings.
Cutting through King's dragon is symbolic of the fact that the Straw Hats are finally close to defeating Kaidou, and Zoro's display of power in One Piece's latest chapter shows that he is worthy of being, together with Sanji, one of the "two wings" that will make the future Pirate King, Luffy, soar.