One Piece was a Japanese manga about the adventures of the protagonist Luffy and the others after the death of One Piece Roger in order to become One Piece. One Piece did not clearly define the four eras, but according to the plot setting, it could be divided into the following stages: 1. The Sky Island Era: Starting from the first time Monchi D. Luffy and the others came to the Sky Island, Luffy became one of the candidates for One Piece. 2. The Valley of God Era: From the second time Luffy and the others came to the Valley of God, one of the "Four Emperors" of the Valley of God appeared-White Beard. 3. Demon Island Era: From the third time Luffy and the others came to Demon Island, one of the "Four Emperors" of Demon Island appeared-- 4. New World Era: Starting from the fourth time Luffy and the others came to the new world, Luffy and the others engaged in an intense battle with the four emperors and other pirate groups. The new world gradually became dangerous. In One Piece, there were many famous representatives of the strong, including: 1. White Beard: The son of Roger the Pirate King, the natural enemy of the Red-haired Shanks, was once one of the four emperors and had the title of " The Strongest ". 2. Red-haired Shanks: One of the four emperors, the man with the name "Shanks" was once an ally of One Piece Roger and the mentor of Luffy and the others. 3. Admiral " Golden Lion " Sabot: A former admiral who had a friendship with One Piece Roger. In order to find the treasure of One Piece Roger, he became a companion of the " Grass Hat Pirates." 4. The leader of the Revolutionary Army, Boya Hancock: The woman with the Devil's Fruit is a powerful pirate and one of the leaders of the Revolutionary Army.