The World Government is an authoritarian organization that has held the reins of the world for multiple centuries. It was formed before the Void Century by twenty rulers who wanted to crush the Great Kingdom. They were successful in their bid, and the kingdom was nearly erased from history.
The World Government is massive, and it employs some of the most powerful One Piece characters. Despite its strength, the organization isn't infallible. In fact, there are many characters in One Piece who could destroy the World Government if they wanted to.
7 Monkey D. Luffy
Monkey D. Luffy is the main protagonist of the series and one of the Yonko. Luffy has all three types of Haki, and he can use the advanced versions of all of them. He also possesses the Hito Hito no Mi, Model: Nika, Mythical Zoan-type Devil Fruit.
The World Government changed its name to Gomu Gomu no Mi to trick people into thinking that it was just an ordinary Devil Fruit. According to the Five Elders, the Devil Fruit has been trying to avoid them. There is a strong chance the Devil Fruit harbors an insane power that could help Luffy destroy the World Government.
6 Blackbeard
Blackbeard is the captain of the Blackbeard Pirates, which is one of the most notorious pirate crews in One Piece. He formed the crew after murdering Thatch and running away with the Yami Yami no Mi.
Blackbeard's Yami Yami no Mi helped him defeat Ace, after which he turned him in to the Marines for a place among the Shichibukai. He then proceeded to raid Impel Down, where he freed the most notorious criminals. Subsequently, Blackbeard made his way to Marineford, and he stole the Gura Gura no Mi. With two powerful Devil Fruits at his disposal, Blackbeard ousted the Whitebeard Pirates and became a Yonko. Imu was seen with a picture of Blackbeard, which implies they consider him a danger to their authority.
5 Shanks
Shanks is among the most popular One Piece characters. He was introduced very early in the series, but much about him still remains a mystery. He used to be an apprentice on the ship of Gol D. Roger, and after the latter's death, he founded his own crew.
Shanks is treated with respect by fellow pirates as well as Marines. When it comes to combat, Shanks is indubitably among the very best. He does not have a Devil Fruit, but his Haki is on a completely different level from most characters. Shanks' burst of Haoshoku Haki was enough to frighten Admiral Ryokugyu. The most astonishing thing was that Shanks was nowhere near Ryokugyu's location.
4 Shirahoshi
Shirahoshi is a character who is often overlooked in terms of threat levels because of her kind nature. She is the princess of the Ryugu Kingdom, but more importantly, she is Poseidon, one of the Ancient Weapons. Shirahoshi has yet to gain control over her powers, although in the Fish-Man Island arc, she gave fans a glimpse of what she was capable of.
As Poseidon, Shirahoshi can call the Sea Kings for aid. Each Sea King is massive and can easily obliterate an island. Once Shirahoshi masters her ability, she can send hordes of Sea Kings to vanquish the World Government and its territories.
3 Monkey D. Dragon
Monkey D. Dragon is the leader of the Revolutionary Army. The organization was founded with the sole purpose of toppling the World Government and exposing its true nature to the people. Dragon's successful endeavors have made him the biggest enemy of the World Government, and it has led to him being called the "Worst Criminal in the World."
Dragon has not indulged in any major battles so far, but the common consensus is that he is saving himself for the biggest fight of them all. Dragon and his Revolutionary Army have already successfully freed many nations, and together they can undoubtedly destroy the World Government.
2 Rocks D. Xebec
Rocks D. Xebec was the captain of the Rocks Pirates. The crew was considered the most dangerous to ever sail the seas. Rocks D. Xebec had complete hegemony over his crew, and no one dared question his decisions. Rocks wanted only one thing: to become the ruler of the world.
He was ruthless in his approach, as evidenced by the fact that he didn't care about attacking the Celestial Dragons in God Valley. While Sengoku confirmed that Rocks is dead, One Piece fans know better than to believe the statement, as there have already been various incidents where characters previously presumed dead turned out to be alive. If Rocks is still alive, he will definitely try to destroy the World Government.
1 ​​​​​​Shiki
Shiki is a legendary character from the old era. He was a member of the Rocks Pirates, but he started his own crew after the God Valley incident. Shiki possesses the Fuwa Fuwa no Mi, a Paramecia-type Devil Fruit that allows him to float himself and non-living objects.
At one point, Shiki tried to team up with Roger. He proposed the idea that his armada, along with Roger's Ancient Weapon, could destroy the World Government. Roger refused his offer, which resulted in the Edd War. Shiki hasn't appeared in the story in the current timeline, but he should still be alive. His achievements include fighting Roger, destroying half of Marineford alone, and fighting Garp and Sengoku. Given his power, Shiki is just as big a threat as the Yonko.