Overseas Battle with the Flying Fish Riders

As the Thousand Sunny continued on its journey to Fishman Island, the ship and its crew aboard encountered many more of the mysterious and spectacular sights of the Grand Line. Among them were a rainstorm that poured down with candy instead of normal rain, a giant sea tanuki, a circular rainbow, and some serpent currents. Eventually, the Thousand Sunny finally reached the area where its next destination was supposed to be, the second part of the Red Line intersecting the Grand Line.[27]

Unable to go any more forward with large rock wall in its way, and with the Log Pose pointing directly below the ship, the Straw Hats decided to deploy Shark Submerge III to investigate the depths below. Due to the extreme pressure of the depths below, the Straw Hats were unable to find anything below five thousand meters under the ship. However, their search brought up an enormous Seaking that threatened to destroy both the Thousand Sunny and its crew. Though the creature was defeated, it spat two things that landed abruptly onto the Sunny's deck. These were Keimi, a mermaid, and Pappug, a talking starfish.

With these new passengers onboard, the crew of the Sunny were promised a reward of great tasting Takoyaki. However before they could be given this treat, they learned that a friend of Keimi and Pappug had just been captured by the Macro Pirates and the Flying Fish Riders. Figuring that these two might know the way to Fishman Island, Nami asked that if the Straw Hats help them rescue their friend, they would show the pirates the way to the underwater paradise. The two agreed to reward the Straw Hats with such along with the promise of Takoyaki. With this, the Thousand Sunny was steered towards the Flying Fish Riders' base with help from a school fish forming an arrow called up by Keimi. Just as the ship was nearing the base, the school of fish leading the Straw Hats suddenly swam away due to them sensing the Flying Fish Riders nearby. Sure enough, the riders soon ambushed the Thousand Sunny and started attacking the ship from atop their giant flying fish. Though a battle between the Straw Hats and the riders ensued, the riders, for some reason, suddenly ran away from the scene as quickly as they arrived.[28]

After sailing awhile after the Flying Fish Rider's last attack, the Thousand Sunny soon reached their base. Though seemingly empty upon arrival except for Hatchan, a previous enemy and the captured friend of the Straw Hats' new traveling companions, the crew guessed the riders were planning an ambush. Their guess was soon verified and a battle between the Straw Hats and the Flying Fish Riders within the base. As the majority of the Straw Hats battled aboard the Thousand Sunny, several things happened. Amongst these in particular was the revelation that the Flying Fish Riders' boss, Duval, had the same face as Sanji's wanted poster and whose grudge against Sanji was the reason why he and his men were attacking the Straw Hats so vigorously. As the battle against Duval and his men continued, the Flying Fish Riders decided to sink the Thousand Sunny by dropping a large anchor on the ship. However through Franky and Usopp's efforts, the ship escaped the attack and instead blew up the Flying Fish Rider's base with an attack of its own from the Gaon Cannon.[10] the Straw Hats eventually defeated the Flying Fish Riders with Sanji rearranging Duval's face with a barrage of kicks. With the matter settled, the Thousand Sunny was then steered towards the Sabaody Archipelago where the solution to getting to Fishman Island could be found.[29]