Episode 520 - Luffy's Promise! The End of the Pirate King’s Journey

Episode 520
Luffy's Promise! The End of the Pirate King’s Journey
Japanese: ルフィの約束！海賊王の旅の終わり
Rufi no Yakusoku! Kaizoku-Ō no Tabi no Owari

Luffy and his crew make their way to a new island where they encounter a group of rebels fighting against a corrupt ruler. The island is home to an ancient temple that holds another piece of the puzzle regarding the legendary treasure. The crew must help the rebels overthrow the ruler while uncovering more about the island’s history.