Ancient Weapons Are Not Myths, They Are Part of History
In the One Piece universe, ancient weapons are not just legends; they are concrete entities directly linked to the dark veil of the Void Century that shaped history. Very few people know about them, and those who do either keep this knowledge hidden or manipulate it. The fact that Roger's pirates learned both the location and purpose of these weapons in Laugh Tale transforms them from mere mythological figures into real threats.
The World Government takes the existence of these weapons so seriously that the Poneglyph in Alabasta, which contains Pluton's plans, is enough evidence to warrant Nico Robin being followed for the rest of her life.
Poseidon: Princess of the Sea Monsters
Poseidon is not an object, but a person: an ancient power carrier who can speak with the voice of the sea. Currently, this power resides in the body of Shirahoshi, the princess of the Ryugu Kingdom. Shirahoshi is powerful enough to command the sea kings with a single word, meaning she can change the fate of warships with a single command.
Every generation that can wield this power is called a “Poseidon,” but the emotional nature of the current Poseidon raises deep questions about whether she can harness her potential. Poseidon can use her power not only physically but also through emotional resonance—this could make her not just a weapon of war but also an instrument of peace. Even the King of Neptune is frightened by the magnitude of his daughter's power, as this ability could turn into an apocalyptic scenario that could submerge the entire world if it falls into the wrong hands.
Pluton: The Sleeping Doomsday Ship
The fact that Pluton's plans are recorded in the Poneglyph in Alabasta proves that this weapon is historically real. However, the actual physical ship is waiting to be built in the depths of the Wano country. After reading Pluton's plans, Franky burned them, but he also left clear signs that he fully understood them—this makes him perhaps the only potential future builder of Pluton.
For Pluton to be revealed in Wano, the massive walls surrounding the country must be destroyed—this symbolizes the opening of both a symbolic and physical “sealed fate.” While Pluton is known to be a warship, this description understates its true nature. This vessel is a weapon of destruction capable of obliterating entire islands with a single shot. Tom (Franky's master) is a descendant of the craftsmen who built Pluto, which means that the ship's plans may have already been put into action in the past.
Uranus: The Hidden Threat in the Sky
We know very little about Uranus, but this does not make it any less dangerous; on the contrary, the uncertainty only amplifies the fear. The nature and shape of the weapon are still shrouded in mystery. According to some theories, Uranus could be a massive energy weapon connected to the sky or an artificial satellite that controls the air – as its name comes from the Greek god of the sky.
The scene where Imu erases the Kingdom of Lulusia from the map in an instant suggests that Uranus was activated by a secret power. This destruction was so sudden and powerful that it resembled a targeted annihilation from above rather than a natural disaster. Clues that Uranus is in the hands of the World Government, combined with Imu's existence and his ability to make decisions without accountability, suggest that this weapon is already in use. Some fan theories suggest that Uranus is a mechanism protecting the “Red Line” ruled by celestial dragons—not a physical weapon, but a threat that maintains the world order.
The Deep Connection Between Poneglyphs and Ancient Weapons
Poneglyphs do not merely recount history; some directly reveal the location or function of ancient weapons. These stones are not meant to be read alone, but rather form a code system that, when pieced together, provides insight into the use of the weapons. Poneglyphs that describe the locations of Ancient Weapons are known as “Information Poneglyphs,” while those that point the way to Laugh Tale are called “Road Poneglyphs”—though both are part of the same system.
The Poneglyph in the Golden City of Shandora, protected by the Shandia tribe, is known as the stone that first clearly inscribed Poseidon's name. This information was personally read by Robin. The fact that Robin is considered a threat by the World Government as the “only person who can read history” indicates a battle over controlling information rather than weapons. Robin's existence is the key that can reveal the weapons, even if she cannot control them. The fact that Ohara was completely destroyed while the Poneglyphs were being deciphered by Oharan scholars shows that access to information was considered more terrifying than the ancient weapons themselves.
Joy Boy, Ancient Weapons, and the Promise
Joy Boy's apology message left on the Poneglyph on Fish-Man Island is related to his promise to use Poseidon. This apology is not just a personal regret; it tells of a delay in a grand plan. The connection between Shirahoshi's Poseidon power and Joy Boy's apology letter suggests that this power was intended to be used for a world-changing event planned a thousand years ago.
The fact that Luffy is seen as “Joy Boy's rebirth” and is the only one who can connect with Poseidon suggests that these ancient weapons could be actively used by the new generation. These ancient weapons may have been created not as tools of physical destruction, but with the purpose of “restoring the world order.” Joy Boy's meaning to them hints at this. These weapons were at the center of the war in the Void Century, but the fact that they were not destroyed, but rather hidden and protected, suggests that their true purpose was not war, but reconstruction.
The World Government's Distorted Relationship with Ancient Weapons
While denying the existence of ancient weapons, the World Government follows a strategy of controlling them rather than destroying them. This contradiction reveals that their greatest fear is not physical destruction but the disruption of order. The World Government's ban on reading the Poneglyphs suggests that they view knowledge as dangerous as weapons. For this reason, Nico Robin is perceived not as a threat carrying weapons but as a threat carrying knowledge.
While the members of the Gorosei and Imu erase countries from the map using a Uranus-like power, they use these weapons not only as “destructive” but also as “regulatory” tools. This turns them into control mechanisms. None of the weapons are openly claimed by the World Government. This strategic ambiguity enhances deterrence. No one dares to oppose them because no one knows which weapon belongs to whom. Vegapunk's research into ancient technology raises the possibility of reproducing weapons like Pluton or Uranus. This points to the convergence of technology and ancient power in the One Piece universe.
The Different Roles and Strategic Powers of Ancient Weapons
Although Pluton, Poseidon, and Uranus appear to belong to the same class, they actually behave like weapons designed for different battle scenarios—one for physical destruction, one for control, and the other likely created for atmospheric or regional domination. Pluton can cause large-scale destruction against a single target, while Poseidon can control all sea routes through hundreds of Sea Kings. Uranus is most likely used for sudden interventions from the air—this trio ensures absolute supremacy across land, sea, and sky.
If these weapons were activated simultaneously, the map of the One Piece world could be completely redrawn. Sea charts would change according to the movements of the sea kings, coastal cities could be destroyed by Pluto, and islands could be erased by attacks from the sky. Poseidon's power operates through “non-human” entities—this aspect makes it a communication-based power rather than one of control. Pluton, on the other hand, is entirely human-made; Uranus, however, leaves open the question of whether it is still supernatural or ancient technology. These differences bind each weapon to a distinct character: while someone wielding Poseidon, with its gentle nature, could usher in an era of peace, someone holding the plans for Pluton could bring about disaster.
Who Can Access the Ancient Weapons?
Nico Robin is the only person who can figure out the location of all three weapons; however, this makes her a “keyholder” rather than a user. Shirahoshi is the current bearer of Poseidon, but how she will consciously use its power remains a mystery—meaning she has potential but lacks direction. Franky claims to have destroyed Pluton's plans, but he may be the only one with the knowledge to rebuild the ship in his mind. This could make him a significant player who could disrupt the balance in the future.
Imu and Gorosei may already be using a Uranus-like power—which shows that weapons are no longer just legends, but are actually part of the game. Monkey D. Luffy's connection with Joy Boy and his communication with Poseidon could make him someone who uses weapons not for war, but to “fulfill the old words.”
Impact on Today's Power Balances
The mere possibility of ancient weapons emerging is creating a domino effect on alliances and war preparations in the One Piece world. Kaido and Big Mom's alliance to reach Pluton in Wano clearly shows that weapons are still being sought and fought over.
The underlying reason for Fish-Man Island's loyalty to the World Government is the presence of Poseidon there. This kingdom is not maintained for strategic reasons but to keep a secret. Wano's closed-country policy is a defense system aimed at protecting Pluton. Those walls are not just to keep enemies out but also to seal off the danger within. If Uranus is truly in the hands of the World Government, this explains why they maintain control without disrupting the balance. The threat is used, but power is not flaunted.
The Technological Foundations of Ancient Weapons and the Oharans' Approach to Wisdom
Although ancient weapons appear to be mystical powers, Pluto's description in particular suggests that they are highly advanced technological products. This gives rise to the idea that the civilizations that lived during the Void Century may have possessed a level of engineering even more advanced than today's. Oharans did not deny the danger of weapons, but they saw the real threat in the restriction of access to knowledge. According to them, it was not the existence of these weapons that was dangerous, but their removal from their historical context and misuse.
Professor Clover's statements also imply that the war in the Void Century was not an ideological conflict but a technological one. Weapons could have been tools used not to establish dominance but to fight for freedom. The reason for Ohara's destruction was not a war preparation but the desire to access information. In other words, the World Government's enemy was not the weapons themselves but the academic memory that could document their existence. The fact that the Pluton plans ended with Franky suggests that there is an heir who continues the philosophy of “not spreading knowledge but entrusting it to responsible hands.”
Vegapunk's Research and Possible Contact with Ancient Weapons
Vegapunk's interest in “ancient technologies” and his attempt to establish a shared consciousness network through Punk Records suggests that he was trying to simulate a Uranus-like control system. The Seraphim project and the Pacifistas bear striking similarities to rumors of robot technology existing in ancient times. This implies that some parts of ancient weapons are still being researched in Vegapunk's laboratories.
The massive energy production system on Egghead Island reinforces the theory that a replica of Uranus is being rebuilt. In particular, the efforts to “control nature” could be modern versions of ancient energy sources. The World Government's granting of broad research authority to Vegapunk may be intended to reduce security vulnerabilities in the reproduction of weapons. However, this is also a tactic to centralize information—because even if Vegapunk is not a threat, the right to choose who is informed belongs solely to the government.
Character Representations and Symbolic Reflections of Ancient Weapons
Pluton represents uncontrolled rage and mechanical power. Its connection to Franky, a character obsessed with explosions, weapons, and the construction process, is not a coincidence but a thematic parallel. Poseidon, on the other hand, embodies power guided by emotions. Shirahoshi's purity suggests that her ability is meant to be a path to salvation rather than a tool of destruction.
The fact that Uranus has not yet been associated with a personality creates strong expectations that he may be linked to a character that has not yet emerged or that he may be the secret identity of an existing character. Although Monkey D. Luffy has no direct connection to any of the three weapons, he has an influence that touches all of them. This implies that the weapons will be activated through themes of “inspiration” and “unity” rather than “leadership.” The ancient weapons are thought to symbolically represent “the power to make decisions.” In other words, using these powers means not only physical superiority, but also the right to determine the future.
Fan Theories and Leaked Clues About the Ancient Weapons
Pluton's physical presence in Wano has led some theorists to believe that the ship was protected by the Kozuki family for years and that its revelation required Wano to “open up to the world.” This suggests that Pluton will awaken in sync with Joy Boy's return. According to some theories, Pluton is not a single ship, but a war system consisting of multiple modules that can be connected to each other. These theories also interpret some abandoned structures in the Grand Line as parts of Pluton.
The strongest theory supporting the idea that Uranus is being used by Imu is supported by the dark silhouette in the sky at the moment the Lulusia Kingdom disappeared. During the event, lightning-like energy waves are seen, suggesting that the weapon manipulates natural energy or weather phenomena. Some fans argue that Uranus is an autonomous, self-operating destroyer connected to an artificial intelligence system. This theory attempts to explain why Uranus is not directly associated with a character and why no one speaks of it.
One of the most intriguing theories is that every ancient weapon has a “counterpart”: if there is a living power like Poseidon, Pluto might have a “living pilot,” and Uranus could awaken when “bound to a will.” This suggests that weapons can be activated not only through physical means but also through a spiritual connection.
Detailed Differences Between the Anime and Manga
When Poseidon's power is first shown in the anime, the size of the Sea Kings and the sound effects are much more exaggerated than in the manga. This emphasizes Poseidon's impact visually, but it can also influence interpretations of the destructive nature of his power. In the manga, the name Uranus is still not clearly associated with an object or person, but in the anime version, the sound effects given when Lulusia is destroyed more clearly imply that the weapon in Imu's hand is Uranus.
In the Wano story featuring Pluto, the anime scenes frequently use transitions that focus on the walls of Wano, providing the audience with a deliberate “visual preview” that Pluto is hidden in the heart of Wano.
Observations About Details That Have Not Yet Been Revealed
There is no absolute training process for Shirahoshi to control her Poseidon power – this potentially opens up the possibility of another character taking on the role of “assistant user” or “coordinator.” It is thought that Pluton may be the “only ship that can cross the seas.” When the Red Line must be destroyed, the revolutionaries or D pirates could use Pluton not only for battle but also to destroy geographical barriers.
The presumed “map-based marking” system Imu used to summon Uranus suggests that the weapon can be locked onto specific coordinates and operate autonomously in target selection. This implies that Uranus may have not only a destructive role but also a surveillance role. Clues suggesting that some archaeologist characters are collecting unseen Poneglyph fragments hint that other individuals with missing information about the ancient weapons may be roaming the universe.