Episode 873 - The Wild Pirate Clash! Luffy Takes on the Toughest Seamen

Episode 873
The Great Pirate Battle! Luffy vs. the Strongest Pirates in the World
Japanese: 大海賊戦！ルフィVS世界最強の海賊たち
Dai Kaizoku-sen! Rufi VS Sekai Saikyō no Kaizoku-tachi

With the guardians defeated, the Straw Hats gain access to the inner sanctum of the island, where they discover a vast underground world. The One Piece’s true nature begins to unfold, and the crew learns that it is not just a treasure, but a powerful force that has the potential to reshape the entire world. The crew must now decide how to handle the discovery.