The first generation (generation I) of the Pokémon franchise features the original 151 fictional species of monsters introduced to the core video game series in the 1996 Game Boy games Pocket Monsters Red and Green (known as Pokémon Red and Blue outside of Japan).
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Second Gen
The second generation (generation II) of the Pokémon franchise features 100 fictional species of creatures introduced to the core video game series in the 1999 Game Boy Color games Pokémon Gold and Silver, set in the Johto region.
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Third Gen
The third generation (generation III) of the Pokémon franchise features 135 fictional species of creatures introduced to the core video game series in the 2002 Game Boy Advance games Pokémon Ruby and Sapphire. These games were accompanied by the television series Pokémon Advanced, which aired from November 21, 2002, until August 28, 2003, in Japan.
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Fourth Gen
The fourth generation (generation IV) of the Pokémon franchise features 107 fictional species of creatures introduced to the core video game series in the 2006 Nintendo DS games Pokémon Diamond and Pearl. Some Pokémon in this generation were introduced in games and animated adaptations of the franchise before Diamond and Pearl, such as Bonsly, Mime Jr., and Munchlax, which were recurring characters in the Pokémon anime series in 2005 and 2006.
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Fifth Gen
The fifth generation (Generation V) of the Pokémon franchise features 156 fictional species of creatures introduced to the core video game series in the 2010 Nintendo DS games Pokémon Black and White. Some Pokémon in this generation were introduced in animated adaptations of the franchise before Black and White.
