One Piece Theory: Uranus Is Already Being Used — And It Changes Everything About the Final War

Every One Piece fan knows the three Ancient Weapons by name — Poseidon, Pluton, and Uranus. We’ve seen Poseidon (Shirahoshi) sob her way to self-realization. We know Pluton is buried under Wano waiting to be called into action. But Uranus? The third and final Ancient Weapon has remained the most elusive secret in all of the Grand Line — until now. Based on the latest chapters of the manga, the evidence is mounting that Uranus is not a weapon at all in the traditional sense, and its reveal might completely shatter everything we thought we knew about the Void Century.

What We Know (And What We Think We Know)

Let’s start with the basics. In the world of One Piece, the three Ancient Weapons were created during or before the Void Century — the 100-year blank period in history that the World Government has desperately tried to erase from collective memory. Poseidon is the ability to communicate with Sea Kings, passed down through the royal bloodline of Fishman Island. Pluton is a warship of devastating destructive capability, blueprints and all. But Uranus? Oda has kept it almost entirely off the table until recently.

The name “Uranus” comes from the primordial Greek deity of the sky — the heavens themselves. This is our first major clue. While Poseidon governs the sea and Pluton represents earthly destruction, Uranus rules the sky. And in One Piece terms, “the sky” carries enormous narrative weight: Skypiea, the Ancient City of Shandora, the Belfry, the Knock Up Stream, and most importantly — the mysterious giant straw hat sealed in Mariejois.

Theory: Uranus Is Not a Ship — It’s a Force of Nature

Here’s where things get interesting. The working theory among the most dedicated fans right now is that Uranus isn’t a physical weapon that can be picked up and pointed at enemies. Instead, it may be something far more fundamental: a power rooted in the ancient relationship between humans and the sky.

Consider what Im-sama did to Lulusia Kingdom. In a single moment, the island was erased from existence by a force that descended from the heavens — a rain of destruction so total that even the ocean where it once stood changed shape. The World Government called it a “natural disaster.” But fans immediately recognized what was actually happening: Im-sama used Uranus.

This changes everything. If Im-sama has been wielding Uranus this entire time, it means the World Government hasn’t just been suppressing history — they’ve been sitting on one of the most catastrophic weapons ever created, using it selectively to keep the world in check. Every “disappearance” of a kingdom or group that got too close to the truth? That was Uranus at work.

The Void Century Connection: What Were They Really Fighting For?

The Void Century ended with the destruction of the Ancient Kingdom and the rise of the World Government. Most theories assume this was a straightforward military conquest — the 20 kingdoms banded together, overthrew a powerful enemy, and then buried the evidence. But the three Ancient Weapons suggest something far more deliberate.

The Ancient Kingdom didn’t just have weapons — they had weapons named after gods. That level of power doesn’t exist in a vacuum. And here’s the theory that’s gaining serious traction right now: the Void Century wasn’t a war over territory — it was a war over who controls the fundamental forces of the world itself.

• Poseidon — dominion over the sea and all life within it
• Pluton — the power to reshape the earth through destruction
• Uranus — control over the sky, weather, and potentially even life and death itself

The Ancient Kingdom wielded all three. The 20 allied kingdoms couldn’t defeat them through conventional warfare alone — which is why they needed treachery, why they needed to rewrite history, and why they’ve spent 800 years maintaining absolute control over information. They won the battle but they’ve been terrified ever since.

Monkey D. Dragon and the Sky: A Connection Too Big to Ignore

This is the part of the theory that makes fans absolutely lose their minds. Monkey D. Dragon — the Revolutionary Army leader, Luffy’s father, the most wanted man in the world — has a power that has never been officially named or explained. But his appearances are consistently accompanied by dramatic weather changes, storms, and winds.

At Loguetown, a lightning bolt shielded Luffy from Smoker. At Goa Kingdom, a massive storm arrived precisely when Dragon needed to escape. Every major Dragon appearance in the manga involves weather on a scale that ordinary Devil Fruits don’t explain.

What if Dragon isn’t just using a weather-based Devil Fruit? What if Dragon’s connection to Uranus is the reason he’s the most dangerous man alive — not because of his Revolutionary Army, but because he is the current inheritor or wielder of Uranus itself? The World Government’s obsession with hunting him down, above even other threats, suddenly makes a lot more sense.

And if Dragon holds Uranus, what does that mean for Luffy? It means the son of Uranus is destined to stand alongside the Sea Kings (Poseidon/Shirahoshi) and Pluton (Wano’s buried warship). The Straw Hat crew isn’t just chasing a dream — they’re literally assembling the three weapons that once shook the world, pointed in a new direction: freedom.

Im-sama’s Endgame and the Final War

Here’s where the latest chapters have fans screaming. Im-sama’s true identity remains unrevealed, but the clues are piling up. The giant straw hat in Mariejois — identical to Shanks’ hat, identical to the hat Roger wore, the same hat now on Luffy’s head — suggests Im-sama has a direct connection to Joy Boy. Not as a successor or ally, but as an adversary who has been waiting 800 years for Joy Boy’s return.

If Im-sama controls Uranus and has been using it to maintain the world order through strategic annihilation, then the Final War isn’t going to be navies clashing on open water. It’s going to be a battle for the sky itself. Luffy’s Gear 5 — his ability to reshape reality through the power of the Sun God Nika — is the only power in the story that has been consistently described as “limitless” and tied to “freedom from all things.”

That’s not a coincidence. That’s Oda’s setup for a confrontation 25+ years in the making.

What the Next Chapters Need to Confirm

For this theory to fully hold water, the upcoming chapters need to deliver on a few specific beats:

• An explicit confirmation that the Lulusia attack was Uranus, not just Im-sama’s personal Devil Fruit
• A clearer look at Dragon’s true power and its relationship to weather manipulation at a Uranus scale
• The Elbaf Arc (currently unfolding) revealing more about the Giant Straw Hat and its connection to the Ancient Kingdom
• Im-sama’s backstory — specifically whether they are a descendant of the 20 kingdoms or something far older

Oda has always rewarded patient readers. Every throwaway line, every background detail, every seemingly random plot point has eventually mattered. The three Ancient Weapons have been on the table since the Alabasta Arc. We’re finally approaching the moment when all three are going to matter simultaneously — and when they do, the One Piece world will never be the same.

The Bottom Line

One Piece is in its final saga, and Uranus is the last major mystery that hasn’t been cracked. The evidence points to a weapon that isn’t a ship or a creature but a force that bends the sky itself — currently in the hands of the World Government through Im-sama, and potentially connected to Monkey D. Dragon on the other side. When this theory gets confirmed, it’s going to reframe every major conflict in the story’s history.

For more One Piece theory deep dives, check out our breakdown of why Shanks might be the final villain and our analysis of Im-sama’s true identity and the final Poneglyphs. The pieces are all on the board — Oda just hasn’t made his final move yet.

What do you think — is Uranus in Im-sama’s hands right now, or is Dragon secretly the key to unlocking its true power? Drop your theory in the comments below.