Eiichiro Oda's One Piece is the story of Monkey D. Luffy, who sets out to sea in the Great Pirate Era with the aim of becoming the King of the Pirates. Luffy gathers various crewmates as he travels across the seas and with each passing arc, he takes a step closer to finding the One Piece and fulfilling his dream.
Although One Piece has a huge number of story arcs, most of them can be grouped to form sagas, as they work toward a particular overarching event in the story. Currently, One Piece is in its 9th saga, with a few more to come after.
9 Thriller Bark Saga - The Straw Hat Pirates Fight Against The Shichibukai Gecko Moria
The Thriller Bark Saga follows the events of the Enies Lobby arc and sees the Straw Hat Pirates getting caught up in the Florian Triangle by accident and eventually lured to Gecko Moria's ship.
Finding out about the horrors that Moria, his Zombies, and his ally, Dr. Hogback caused together, Luffy and the crew decide to defeat them and, in doing so, free many people from his grasp. What's more, the end of the arc is marked by a brilliant fight between Zoro and Kuma where the former sacrifices himself for the crew. To top it all off, Brook joins as the Musician of the pirate crew.
8 Alabasta Saga - The Straw Hats Take Vivi To Alabasta & Save The Kingdom
The second saga of the story, the Alabasta Saga introduces Princess Vivi as an important character, and she meets the Straw Hat Pirates at Whiskey Peak. From there, the crew travels to Alabasta and helps her stop a rebellion in her country, which is followed by taking down the man behind it all, Sir Crocodile.
This saga is the first time Luffy and his crew fight a Shichibukai group, and as expected, it is packed with high-octane action and robust emotions.
7 East Blue Saga - Luffy Travels Across East Blue & Finally Enters The Grand Line
The very first saga of the series, the East Blue Saga sees Luffy set out on his journey in East Blue and recruit the first 4 crewmates across this sea. At Shell's Town, Roronoa Zoro joins the crew, followed by Nami at Orange Town.
As they arrive at Syrup Village, the sharpshooter Usopp joins the group after saving the village from Captain Kuro, and finally, the chef of love, Sanji joins them at Baratie. Acquiring the very basic crew members, Luffy sails for Logue Town and enters the "pirate's graveyard," the Grand Line.
6 Fishman Island Saga - The Crew Reunites At Sabaody Archipelago & Sets Off To Fishman Island
The Fishman Island Saga is the first Saga into the New World and it consists of two arcs in "Return to Sabaody," and "Fishman Island."
After the two-year training period, the Straw Hats are finally back, and they immediately set sail to Fishman Island. Met by the hatred of Hody Jones, the crew gains the support of Fishmen and takes an essential step towards mending the relationship between them and humans. The legend of Joy Boy and the revelation of the Ancient Weapon Poseidon is also revealed to the fans.
5 Dressrosa Saga - Luffy Allies With Trafalgar Law & Makes An Enemy Out Of Donquixote Doflamingo
The Dressrosa Saga consists of Punk Hazard and Dressrosa as the two story arcs. Being the first two islands the crew visit in the New World, the intensity is amped up by a significant amount, and the stakes get bigger than ever.
The Punk Hazard arc sees Luffy ally with Trafalgar Law in order to take down Yonko Kaido, however, Doflamingo needs to be taken care of first. Consequently, the Dressrosa arc is where Donquixote Doflamingo is faced by the Straw Hat Pirates, and his tyranny over the island comes to an end.
4 Sky Island Saga - The Straw Hats Travel To Skypiea & Light The Fire Of Shandora
The Sky Island Saga consists of Jaya and Skypiea arcs and is quite easily the best in the story when it comes to storytelling and world-building.
The arc introduces the sky races to the fans, along with the legend of Shandora, an ancient city that fought against the World Government during the Void Century. Full of adventure and great lore, the Skypiea Saga sees Luffy fulfill the ages-old promise between Noland and Calgara, and ring the fire of Shandora.
3 Water 7 Saga - The Straw Hats Look For A Shipwright At Water 7 But Mystery With Nico Robin Unfolds
The Water 7 Saga is, for many One Piece fans, the best in the story, and this saga delivers like no other when it comes to conflict between the crew members and intense fights.
From Luffy and Usopp's fight to Robin's disappearance and eventually invading Enies Lobby to get her back, this arc has it all and had thus gone down in history as one of the greatest in the entirety of fiction.
2 Four Emperors Saga - Luffy & The Crew Finally Fight Against The Four Emperors
The Four Emperors Saga is currently ongoing and it includes Zou, Whole Cake Island, and Wano Country arc of One Piece, all of which are highly rated among the fans.
After allying with Law, this Saga aims to take down Yonko Kaido at Wano. Before that, however, the crew finds out about the Road Poneglyphs and then sets off to retrieve Sanji from Whole Cake Island. Finally, at Wano, the alliance clashes against Big Mom and Kaido.
1 Summit War Saga - Luffy Finds Out About Ace's Imminent Execution & Attempts To Rescue Him
The Summit War Saga is the end of the first half of One Piece and arguably the greatest part of the story to date. After their arrival at Sabaody Archipelago, Luffy is separated from his crew and is sent to Amazon Lily, where he finds out about Ace's execution. Seeking help from Boa Hancock, he infiltrates the Great Prison, Impel Down, to save Ace and follows him all the way to Marineford.
Caught in an era-changing war between the Whitebeard Pirates and the Marines and Shichibukai, Luffy rescues Ace, only to see him die in his arms moments after.