Episode 706
Luffy’s Ultimate Test! The Battle to Become the Pirate King
Japanese: ルフィの究極の試練!海賊王になるための戦い
Rufi no Kyūkyoku no Shiren! Kaizoku-Ō ni Naru Tame no Tatakai
As the battle on the island escalates, the Straw Hat Pirates discover that the treasure is a weapon with the power to destroy entire islands. The island's ruling faction attempts to use it to assert control over the Grand Line, but Luffy and his crew refuse to let such a weapon fall into the wrong hands. They must prevent its activation while dealing with hostile factions who believe they can control the power for their own benefit.