At around 300 Justice Island is basically over, Luffy and the gang saved Robin from CP9, but encountered a siege of warships, and in the nick of time it was the Merry that saved everyone. Upon returning to the Water Capital the Merry was magnificently sacrificed, after which it went into a rest and recuperation chapter. Before leaving Suikoden, Frankie builds a new ship for Luffy and the others, the "Sunny Sunny", and Luffy and the others get on board and become new partners. The bounty for everyone was also raised during the battle.
After that, the group continued on their journey and fell into the Devil's Triangle. In the waters they encountered the mysterious Skeleton Gentleman-Brook. From Brooke's encounter, he learns about Terror Island and the capture of Shadow, and after Brooke leaves, the group boards Terror Island. On Terror Island, Sanji, Sauron, and the others had their shadows seized by one of the Seven Martial Seas, Moonlight Moria, whose goal was to capture Luffy's shadow and thus manipulate the sleeping giant Oz. In the end, the combined forces of the group defeat Oz and Moria. In the process, the focus is on Brooke's past, and in a stroke of God, Oda pulls the thread back to Rabu, the beginning of the Great Voyage. Eventually Brooke joins everyone.
But after defeating Moonlight, when the group is exhausted, an even greater foe comes to them - Tyrant Bear. In the end, it was Sauron who sacrificed his courage for the safety of the group.
After the end of Terror Island, the group continued their adventure to the Shampoo Islands. Luffy drew a siege from the Navy for teaching a lesson to the Skrulls. In the end, the group was unable to defeat Tyrant Bear, and one by one, their partners disappeared in front of Luffy, and the Straw Hat Pirates were separated.
And then the plot starts from the undersea prison and steps into the big event.