The shonen juggernaut One Piece houses a slew of weapons, from mountain-splitting katana to cyborg soldiers. Eiichiro Oda's award-winning manga, lauded for its masterful world crafting and imaginative storytelling, is filled with ingenious creatures, punny attacks and unique weapons. Given One Piece's action-adventure nature, however, intriguing aesthetics aren't enough for these elements to stand out. Among the thousands of weapons in the series, the mysterious Ancient Weapons stand on top.
Getting stronger in One Piece does not necessarily imply acquiring greater power or technique. Granted, eating a Devil Fruit will grant an instant power boost but acquiring and improving weaponry is also a viable route -- just like Nami has been doing. That's also the reason why numerous characters, including the already formidable Crocodile, covet these destructive weapons. Despite and perhaps because of their rumored might, there is still a lot left unknown about these Ancient Weapons.
The Ancient Weapons in One Piece are three legendary weapons rumored to have enough power to cause mass destruction. Named Pluton, Poseidon and Uranus, they are said to have been operated during the Void Century, which is the primary reason the World Government strictly forbids study of this time period. Since the Void Century is immortalized through Poneglyphs, learning the language is also forbidden by extension -- and the reason Nico Robin is hunted by the World Government. Of the three, only Poseidon has been fully explored, while mere bits and details are known about Pluton.
Pluton was the first Ancient Weapon to be introduced in One Piece. It is said to be the world's worst battleship as it can easily eradicate whole islands at once -- the very same weapon Crocodile and Spandam sought after. The Poneglyph in Alabasta details a hint at its location, though the exact point is yet to be discovered. Since this Ancient Weapon is designed and constructed in Water 7, its blueprint is passed down from one shipwright to another as a countermeasure should the Ancient Weapon fall to the wrong hand. That blueprint ultimately came into Franky's possession, but the half-cyborg decided to burn it.
Poseidon was the next Ancient Weapon to be revealed. Its existence is first mentioned on the Poneglyph in Skypiea, then was fully explained on the Poneglyph in Fish-Man Island. Unlike Pluton, Poseidon was a living being. She was a mermaid princess who had the ability to talk to and command Sea Kings. That ability didn't simply vanish after her death, however; it was passed down to the next generations of the royal family and is now possessed by the giant mermaid princess Shirahoshi, who also inherited the title "Poseidon." Uranus, however, still lurks entirely under the radar. Other than its name, everything about it remains a mystery.
The existence of the Ancient Weapons poses enough threat for the World Government to ban even small attempts of unveiling them. Given the looming large-scale battle One Piece seems to be brewing, it is perhaps not cynical to believe that full details about these weapons of mass destruction will soon be revealed -- and perhaps One Piece fans will soon see them in action.
