POSSIBLE SPOILERS!!!
There are three Ancient Weapons in the One Piece world: Uranus, Pluton, and Poseidon. Poseidon is a Mermaid that appears every few hundred years. Poseidon has the ability to communicate with sea kings and maybe even control them. Pluton is said to be a massive and powerful warship which was built in Water 7 during the Void Century and is currently at Wano. Uranus is completely unknown and has been mentioned very few times in the series. Uranus, Pluton, and Poseidon are named after Gods in mythology. Ouranos was the Primordial Greek God of the Sky. I think Uranus is a weapon that allows one to manipulate and control the weather in many ways. What do you think?