The world of One Piece is filled with mysteries, especially those concerning the World Government and the Void Century. The very first hint fans got of this was the Alabasta arc, where the Poneglyphs and the idea of the Void Century were introduced.
Ever since then, the story has slowly been diving into deeper mysteries. The Skypiea arc told the fans about the Great War that Shandora fought in, the Water 7 arc introduced an Ancient Weapon, and the Marineford arc declared the coming of a massive
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