The Yonko, the four most formidable pirates in the world of One Piece, hold dominion over the New World with unrivaled authority. Even the Navy is wary of engaging directly with them. These individuals are amongst the most powerful characters in the entire One Piece universe, largely due to their mastery of Haki.
While nearly all Yonko possess exceptional Haki, the level of control they have over this skill varies. Fans have witnessed most Yonko exhibit Haki at an advanced level, but only a select few can truly claim to be among the absolute strongest.
6 Blackbeard
Blackbeard, a formidable character in the world of One Piece, ascended to the position of Yonko after the events of the Pirate Island and the Rocky Port Incident. What sets him apart is his possession of two extraordinary Devil Fruits - the Gura Gura no Mi and the Yami Yami no Mi. These Devil Fruits are considered the strongest in their respective categories. While Blackbeard's Haki, a form of spiritual energy, remains undisclosed in the story, it is anticipated to be overpowering due to his ambitious nature. However, fans have yet to witness significant displays of his Haki, making it difficult to accurately gauge its true strength at this point.
5 Big Mom
Big Mom, a former Yonko and one of the strongest characters in the world, possesses an unstoppable force and a notorious bounty of 4.388 billion berries. Her incredible power stems from her Devil Fruit called the Soru Soru no Mi, but she also exhibits exceptional proficiency in all three forms of Haki. Surprisingly, Big Mom rarely showcased her advanced version of Conqueror's Haki during her battle against Kid and Law, leading fans to speculate that she relies more heavily on her Devil Fruit ability than her Haki skills.
4 Luffy
Despite recently becoming one of the Yonko, Luffy is undeniably one of the most powerful pirates in the world of One Piece. Alongside his legendary Devil Fruit, Luffy possesses exceptionally strong Haki abilities. In fact, he has mastered all three forms of Haki and continues to strengthen his Conqueror's Haki. Luffy's Haki proved formidable in his confrontation with Kaido, showcasing its impressive power.
However, it is worth noting that Luffy's Haki still pales in comparison to that of Kaido. This was evident during their clash, and it was ultimately Luffy's Devil Fruit that allowed him to gain an advantage over the Yonko. Nevertheless, Luffy's journey is far from over, and it is expected that by the end of the story, his Haki will become the strongest of them all.
3 Kaido
Kaido, one of the Four Emperors of the Sea, was known as the Strongest Creature in the World and was regarded as the strongest among the Yonko. Along with his ability to transform into a dragon using his Mythical Zoan Devil Fruit, Kaido possessed an exceptionally powerful Haki. He had mastered all forms of Haki, including Conqueror's Haki, and his control over Conqueror's Haki Infusion was unparalleled. In comparison to Luffy, Kaido's Conqueror's Haki was at a higher level and displayed a greater level of refinement. Even in Luffy's Nika state, it was evident that Kaido was still the dominant force when it came to Haki.
2 Whitebeard
Whitebeard possessed immense power, both through his Devil Fruit ability and his formidable Haki. His Haki was particularly potent during his prime, evident in his intense clash with Roger. Although his Haki may have been slightly inferior to Roger's, it was still incredibly formidable.
1 Shanks
Shanks, one of the current Four Emperors, possesses an unrivaled mastery of Haki. Despite lacking a Devil Fruit ability and having only one arm, his immense power is evident. Shanks has honed all facets of Haki to a remarkable degree, with his proficiency in both Future Sight Observation Haki and Conqueror's Haki Infusion standing out as the best seen in the story thus far.
Notably, Shanks can peer into the future for a duration exceeding 10 seconds, a truly astonishing feat. Additionally, his Conqueror's Haki possesses such overwhelming strength that a single strike from him is capable of rendering a pirate valued at 3 billion berries unconscious. What's even more remarkable is the fact that Shanks has yet to unleash his full power, suggesting that the true extent of his Haki remains unseen. Given his status as Roger's apprentice and his utilization of the same fighting style, it is highly plausible that Shanks' Haki is on par with that of the legendary pirate. Undoubtedly, among all the Yonko in One Piece, Shanks possesses the most formidable Haki.