Pluton

Pluton is one of the three Ancient Weapons, alongside Poseidon and Uranus. Pluton is a huge warship capable of mass destruction, constructed long ago in the city of Water 7 in the Grand Line. It is said to be capable of destroying whole islands. Pluton was first mentioned by Crocodile when he questioned Nefeltari Cobra of its whereabouts. It is supposed to be a large warship of some kind. Not much else is known about it.

Its power was as dangerous as other weapons like Poseidon, who herself had the power to sink all the world's islands into the ocean, although exact details of its capabilities remain unknown. Whoever controlled the weapon had the potential to conquer the world in the process and in the wrong hands would be dangerous. Likewise, Pluton also had the ability to do as much damage to the world. Furthermore, because the blueprints remained in existence even after the ship was built, whoever possessed the blueprints to the vessel would have the potential to build a fleet of vessels with the same destructive abilities as each other. The blueprints had been preserved as a means of bringing Pluton back into existence should the world ever need her to fight the weapons, including the original Pluton itself. At this point, however, the blueprints which were used to create it are now destroyed while Pluton itself is still asleep. Pluton was designed and constructed on Water 7 during the Void Century, and became inactive after the war. As a reaction to the threat Pluton carried, the World Government used the existence of Pluton, Poseidon, and Uranus as the primary reason for banning Poneglyph research. What happened to it after the war has not yet been revealed, but it is supposedly hidden somewhere in Alabasta, and the Poneglyph telling its location is hidden in the kingdom's royal tomb.

Unlike Poseidon, whose ability was passed down the Ryugu Kingdom royal family bloodline, Pluton was said to be an object, meaning the only way a second instance could be created was by reconstruction. The weapon's blueprints were secretly kept in Water 7. They had been passed down in a line of incredible shipwrights for centuries before eventually falling into the hands of the legendary shipwright Tom. The duty of the shipwrights was to guard the blueprints and prevent them from falling into the wrong hands. Also, they were supposed to use them to construct a second Pluton should the first weapon ever be revived. Eight years before the current storyline, Spandam, the chief of CP5, appealed to the Gorosei to gain control of the Ancient Weapon in order to bring the Great Pirate Era to an end. His research led him to Tom, from whom he demanded the blueprints. Tom feigned ignorance, but when Spandam left, he entrusted the blueprints to his apprentices, Iceburg and Cutty Flam, to ensure that they would not fall into the Government's hands. Days later, when Spandam framed Tom and arrested him, and Cutty Flam suffered a seemingly fatal accident after pistol whipping Spandam, Iceberg alone kept the blueprints. Three years later, during which Spandam had become chief of CP9, he sent four agents undercover into the city to locate and obtain the blueprints. Four years after his assumed death, Cutty Flam returned to Water 7, and secretly met with Iceburg, who gave the blueprints to him for safekeeping. Iceburg requested that he no longer use his real name but only go by the nickname that he had given him, Franky, and leave the island to ensure that the Government would never find the blueprints. Out of necessity to avoid being arrested, he followed the first part of the advice, but refused to leave the island, much to Iceburg's ire.