An Evolutionary Stone is a special item in the Pokémon series that allows certain Pokémon to evolve into their next forms. Each type of stone corresponds to specific Pokémon, such as the Fire Stone for evolving Vulpix into Ninetales or the Water Stone for evolving Psyduck into Golduck. These stones are often found in various locations throughout the games, making them valuable for trainers looking to enhance their Pokémon's abilities. In addition to the main series games, Evolutionary Stones also appear in spin-off titles and related media. They play a crucial role in the evolution mechanics of Pokémon, providing a straightforward way for trainers to evolve their Pokémon without the need for leveling up. This feature adds an exciting layer to gameplay, encouraging exploration and strategy in choosing when to use these stones.