About the Marineford Arc
The Marineford Arc is the 22nd story arc of the manga and anime One Piece, and the fourth story arc of the Summit War Saga.
Having failed to reach Ace before he was transferred, Luffy and his companions escape from Impel Down and travel to Marineford, the base of Marine Headquarters. With the odds stacked high against him, the imminent threat of Whitebeard, and the ulterior motives of pirates that wish to overthrow the Emperor, Luffy struggles to hold his own in this titanic clash of powers.
All around the world, people voice their opinions on the execution and if Whitebeard will really show up. A few doubt his strength due to his old age and the number of the Marine forces. Others, who personally met Whitebeard and even retired from piracy just by being around him, think otherwise. Even children know of Whitebeard's raw strength and sing a playground song about him. Meanwhile, the inhabitants of Marineford, a city where the families of Marines reside, have been evacuated due to the coming war. On the Sabaody Archipelago, monitors have been set up to broadcast the execution to its inhabitants as Ace arrives at the execution stand. The patrol ships sent to deal with Whitebeard's forces are sunk and never heard from again. Thus, Marineford is understandably on edge as the three hours until the execution countdown.
John Giant rallies his forces as a staggering one hundred thousand elite troops prepare for battle. Fifty Marine ships are stationed around the island, with cannons lining the coastline. The remaining Warlords of the Sea (Kuma, Moria, Doflamingo, Mihawk, and Hancock) are at the forefront of it all. Ace is located atop the execution stand at the rear of the island. Watching over him are the three Marine Admirals: Kizaru, Akainu, and Aokiji. With this, nearly every justice force imaginable is gathered, waiting for Whitebeard to make his move. On the Tarai Current, Luffy and the Impel Down escapees have finally reached the gate to Marineford. Jinbe tries to think of a way to penetrate it while Buggy rallies his followers.