The world of One Piece established the Three Big Powers to the fans before the 2-year timeskip of the series. These Three Big Powers were, of course, the Yonko, the Marines, and the Shichibukai. The Shichibukai were allied with the Marines and the World Government, and together, they helped deter the Yonko and bring about a balance to the world. However, after the recent Reverie, the Shichibukai system was abolished, and the World Government decided to use the newly created power of the SSG, called the Seraphim, to bring about a new balance to the world.