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Bury them in the ground and wait a few days, come back later and dig them up and if u trade them to hikers you can get bigger and better decorations for your secret base. They grow pretty fast, i already have some lvl 99 spheres! enjoy

Bury a sphere in the ground and come back another day and it will be bigger. Tip: bury more than 1 in the same hole, but it must be the same type, color. You can trade the hikers for different things to use in your base. Have fun and dig....

spheres are good. If you put them on the ground they will grow bigger everydaty. THe hikers that are on the underground trade them. You can get a digger drill if you have big size spheres