The most interesting thing about Uranus is that we have heard and seen almost nothing about it. Pluton was introduced quite early, in Alabasta and Poseidon was first mentioned in Skypiea. But Uranus is only mentioned directly in Fishman Island.
We later learned in Water 7 and Enies Lobby, that Pluton was a battleship, to which blueprints existed. These blueprints were in the hands of Tom’s clan and passed down to Franky and Iceberg. In Fishman Island, we learned that Poseidon is the mermaid princess. Shirahoshi.
We still don’t know what Uranus is, but there are a few popular theories. The most popular is the idea that if Shirahoshi is Poseidon and the 1st Sovereign One, then Momo is likely Uranus and the 2nd Sovereign One. Both can not only heat the VoAT, but they can also converse with it.
This remains a very strong idea and would tie in well with the events of Wano and the prophecy or the resurgence of Joyboy. Both Wano and Fishman Island want to open their borders ‘at the promised time.’
The Ancient Weapons have been teased as though they will soon be revealed, through Big Mom and Kaido’s declaration that they intend to find them. It’s highly likely that they will become implicated in the finale of Wano.
However, there is another very interesting theory, that Momo is not Uranus, though he may still be the 2nd Sovereign One. What if Uranus is behind the creation of the giants? In mythology, Uranus is associated with this.
“From the blood of Uranus that spilled unto the earth came forth the giant.” What if Uranus is a naturally occurring substance that is responsible for the natural occurrence of giants? The theory points out the idea that perhaps this comes in the form of sweet fruits.
These fruits, called ‘Mana’ are fruits that come from Ash Trees. ‘Mana’ is a Polynesian word for ‘source of power’. These fruits look remarkably like both Chopper’s Rumble Balls and Ceaser’s NHC10 ‘candies’. These fruits are known as ‘sweet fruits’, would connect with the parallel that exists between Chopper, the kids from Punk Hazard, and Big Mom. All show an addiction to ‘candy’. Although the kids are under the impression that the drug is ‘candy’.
If these fruits are said to come from an Ash Tree, then it is possible that such a thing may be found on the giant tree of Elbaf. This tree is likely based on Yggdrasil from the Norse myth. A giant Ash Tree, on top of which lies Asgard. Realm of the Gods. If this is the case, it may explain why it seems that Uranus has only once been directly named, because it’s been getting referenced constantly through different contexts. It may be the substance that created the giants.
If this is the case, it would explain why the World Government has been trying for centuries to accomplish the artificial creation of Ancient Giants from humans. They are trying to recreate Uranus. Law talked about it with Robin during the Punk Hazard Arc.
This would connect well with the fact that the World Government was also trying to obtain the blueprints to Pluton so that they could prevent anyone from making a countermeasure when they seized the original from Alabasta. The World Government obtaining Pluton is likely to tie into the Great Cleansing. It seems to be foreshadowed that this will begin with Alabasta and would tie into the fates of Cobra and Vivi.
The events of the Great Cleansing would begin due to the collapse of the Balance of Power. This is the consequence of both Big Mom and Kaido being defeated. Just like the Warlord system, the Yonko lose credibility. The intention of the raid is to open the borders of Wano so that Joyboy may return and the Two Sovereign can meet. This ties things back to Momo and Shirahoshi. It implies that Shirahoshi will be called to Wano.
However, the unintended side effect of opening the borders and succeeding in this raid, is that it will result in the collapse of the Balance of Power and the invasion of Wano will begin, as well as places like Alabasta. This implicates the possible capture of both Poseidon and Pluton but once again, what about Uranus? Well, it may be the case, that Big Mom is the key to the successful creation of Artificial Giants. She is a giant human and likely has naturally occurring Lineage Factor mutations.
If Big Mom were to be defeated, it’s possible that she may be captured. This would potentially create a parallel to Kaido, whereas he was experimented on to perfect artificial fruits, Big Mom may be experimented on to perfect artificial giants. If this is the case, then putting all this together, it’s possible that in the finale, or as a consequence of Wano, a domino effect will begin, that may lead to the World Government successfully obtaining all three Ancient Weapons!
Alternatively, it’s possible that the World Government will only obtain Pluton and Uranus. The fact that Caribou currently carries information on Poseidon, and the possibility that Poseidon is coming to Wano, presents the possibility of someone else capturing Poseidon.
In conclusion, I believe that the final Ancient Weapon, Uranus, is a substance that is responsible for the creation of the Giants. The World Government has been trying to remake it The finale of Wano may implicate all 3 Ancient Weapons falling into the wrong hands. The ‘Day of Disaster’.