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The third generation (Generation III) of the Pokémon franchise features 135 fictional species of creatures. The first Pokémon, Treecko, is number 252 and the last, Deoxys is number 386. Some Pokémon in this generation were introduced in animated adaptations of the franchise before Ruby and Sapphire.
See also: Pokémon the Movie: Volcanion and the Mechanical Marvel, List of generation VI Pokémon, Pikachu, Pokémon Unite, List of generation IX Pokémon, and List of Pokémon.