Since the launch of Pokémon X and Y, over 90 million Pokémon have been traded using the Global Trade Station feature. Once that number reaches 100 million, the Pokémon Company will distribute a brand new pattern of the Bug/Flying Type Pokémon, Vivillon, called "Fancy Pattern."
Vivillon is a special Pokémon due to its many different wing patterns that were introduced in Generation VI . Their patterns are different depending on which area in the game it reaches its final evolution, but it's also different when traded from one real-world location to another. For example, a Spewpa from Canada will evolve with a wing pattern and colorization different from one in Japan. Overall, there are a total of 20 Vivillon patterns that can be collected.
Since its November release, Pokémon X and Pokémon Y have sold over 11 million copies and are the best selling 3DS titles to date.