Episode 405 - The Pirate King’s Final Stand! Luffy’s Ultimate Test

Episode 405
The Pirate King’s Final Stand! Luffy’s Ultimate Test
Japanese: 海賊王の最後の戦い！ルフィの究極の試練
Kaizoku-Ō no Saigo no Tatakai! Rufi no Kyūkyoku no Shiren

The battle with the mercenaries continues, and the crew realizes that the island holds more secrets than they initially thought. The mercenaries have a secret agenda, and it becomes clear that the weapon they are after is far more powerful than anyone imagined. The episode highlights the crew’s bravery in protecting what they believe is right.