Rain formed when sunlight heated water on Earth, evaporating it into water vapor. When that vapor met cold air high above the ground, it condensed into tiny droplets, which then became raindrops.
The Land of Wind's coast certainly received plenty of sunlight, but that was too slow. Uzumaki Gamu wanted to accelerate the entire process in one go, so he used Boil Release to evaporate a massive amount of seawater!
With Tailed Beast Power backing his Boil Release, evaporating hundreds of thousands of tons of seawater was no problem.
Watching the steam rise into the sky and gradually form clouds, Reto finally understood what Uzumaki Gamu was planning-artificial rainfall!
Just then, Uzumaki Gamu shouted from below, "Hey, don't just stand there watching! Use your Wind Release to guide the steam toward the lake!"
"Oh!" Reto immediately pushed his Wind Release to its limit, driving the water vapor toward the lake. Soon, rain clouds formed above it, and drops began pattering down!
Uzumaki Gamu's plan was simple: first, have Hashirama create a huge basin. Then, evaporate seawater himself. Finally, have Reto, their Wind Release expert, rapidly gather the steam into rain clouds and guide them over the lake, where they would condense into rain. And then... rainfall!
Since Hashirama had already altered the soil below with Earth Release, it could now hold all that rainwater without leaking. At this rate, it would soon become a proper lake.
Normally, this method of producing rain would be impractical. But in this world of supernatural powers, the three of them could pull it off!
Come to think of it, Uzumaki Gamu could apparently handle Reto's part himself. Why involve him at all?
Well, it gave him a taste of the experience and let him feel involved... It also meant the Land of Wind had