One Piece: Season 23, Episode 1169

23 - 1169: The Legend Lurking in Elbaph - The Identity of the Mountain-Eater

While exploring the abandoned castle, Luffy and the others find a strange mark on the floor of the throne room and hear a mysterious voice out of nowhere. At the banquet, Oimo tells Usopp the tale of a legendary man linked to the Pirate King.