The Sun Stone was first introduced in Generation II as another Elemental Stone that could be used to evolve a couple of unique Grass-Type Pokémon. The stone bears a striking resemblance to the sun, it's orange and spherical, with ray-shaped edges, and is said to harbor a deep connection with the giant star. It is one of the five Elemental Stones which can be bought in stores only in Generation IV.
Two more Grass-Type Pokémon were added to the list of Pokémon that can evolve by using a Sun Stone in Generation V.
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