Summary
The Yonko are incredibly powerful individuals that the fans have seen quite a lot of in the post-timeskip ofOne Piece.These are mighty pirates who rule the New World like Kings and their influence is such that even the Marines do not dare to directly take them on in battle without orders.
The Yonko are mighty powerful, and much of that is down to their incredible Devil Fruits, as well as their tremendous usage of Haki. Over the years, fans have seen quite a lot of nearly all the Emperors, and they certainly do have some special powers up their sleeve. In fact, every Yonko has an ability that makes them unique.

Fruit
Chop-Chop Fruit
Undoubtedly, Buggy is the weakest of all the Emperors that the fans have seen in One Piece. His rise to Emperor status is an entire fallacy, and fans know that hedoes not hold up to an actual Emperorin any way. Still, Buggy does possess this title, and he has the power of the Bara Bara no Mi at his disposal.
When it comes to his strongest attack, fans know that he possesses the Muggy Ball, which he utilized extensively in the Impel Down Arc. To be fair to Buggy, he might have leveled up in terms of attack power after the timeskip of the series, however, fans have not seen him in combat yet to conclude that he does possess stronger techniques.

Dark-Dark Fruit, Tremor-Tremor Fruit
Blackbeard has not revealed his full deck to the fans just yet. However, fans do know that he possesses two mighty abilities, and those are of the Logia type, Yami Yami no Mi, and the Paramecia type. In terms of utility, his Yami Yami no Mi is the strongest power that he has.
He can essentially nullify any other Devil Fruit ability and use Black Hole to suck in just about everything. However, in terms of attack output,Blackbeard’s strongest power is Gurash, which he utilized against Law. This is essentially a tremor that can sink islands with ease. He likely has stronger abilities up his sleeve that he has not shown to the fans just yet.

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Shanks is one of the strongest Emperorsand potentially thestrongest Emperor in the seriesright now. He does not have any Devil Fruit power, and as a result, Shanks does not rely on anything other than Haki in combat. Given the Shanks is a master of Haki, he utilizes Conqueror’s Haki as his biggest asset in combat.

His strongest power that the fans have seen so far came against Eustass Kid, and it is the same one that Roger utilized against Oden as well. Shanks’s strongest attack is, by far, Kamusari. This powerful blow was able totake out both Kid and Killer at the same time.
Tremor-Tremor Fruit
Whitebeard was the former user of the Gura Gura no Mi, and fans know that he possessed incredible might that could even destroy the entire world.
Whitebeard’s strongest technique was Shima Yurashi, which saw him grab onto thin air and tilt his surroundings. He could cause earthquakes and seaquakes and tilt the entire ocean if he so desired. Sadly, even Whitebeard’s strongest could not help him survive against his enemies, and the power of Tremor-Tremor Fruit and Shima Yurashi, along with it, went to Blackbeard.

Soul-Soul Fruit
Big Mom is a woman with many weapons to utilize. In fact, in her case, it is very hard to figure out what her strongest attack is. Big Mom can fight in a plethora of ways, and each attack of hers is stronger than the previous one. She’s also very versatile in combat.
For instance, anyone who fears Big Mom even the slightest is essentially dead right on the spot in combat against her. She canmake use of Soul Pocus to take their soul away and kill them.However, when it comes to stronger individuals, Big Mom has other weapons up her sleeve. In the fight against Kid and Law,Big Mom made use of Misery, which was a combination of her special homies and was strong enough to overpower even Eustass Kid and Trafalgar Law.

Fish-Fish Fruit
Kaido is quite easily the Yonko that the fans have seen the most of. He revealed his entire arsenal of techniques in the Wano Country Arc, and it is easy for the fans to see that his strongest technique is, by far, Kaen Hakke. This technique was a byproduct of Shoryu Kaen,where Kaido created a giant fire dragon capable of melting Islandsjust by passing over them.
This technique was incredible, however, it was not strong enough to overcome Luffy’s usage of the Hito Hito no Mi, model: Nika, as well as his Haki.
Gum-Gum Fruit
Luffy has recently ascended to the level of a Yonko, and fans know that he is incredibly powerful.Luffy’s strongest technique is, by far, Bajrang Gun.
He utilized this technique in his fight against Kaido, and this technique essentially saw him create a fist as big as an entire island and then bring it down on the Yonko. Essentially, itdefeated Kaido and created a hole in Wano, sending him down to the underground volcano.