Thunder Stone: A stone that is used in most of the Pokémon games in the series. It is useful to trainers if they have a 1st or 2nd evolution category Electric type Pokémon like Pichu and then Pikachu because its main use is to evolve a 1st or 2nd category Electric Pokémon to become stronger without having to level it up as high. You can't buy it in Diamond and Pearl, you can only find it by exploring underground and digging up items.
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