A new Team Medallion item recently made its Pokémon GO debut. This special item allows you to change your team for 1,000 PokéCoins. It is now available for purchase and only one Team Medallion can be used in a single year. With the Team Medallion, you now have the option to be on Team Instinct, Team Valor or Team Mystic:
https://twitter.com/Frostbyte57/status/1102988120646189056
Source: @PokemonGoApp
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