Akin to how six different Unown appeared at the first-ever Pokémon GO Fest to spell out the word Chicago, as well as in London with the word Europe, a similar occurrence is currently taking place in Anaheim, California, at the 2017 Pokémon World Championships to spell out the word Worlds. This is part of the ongoing celebration of the one-year anniversary of Pokémon GO.
Source: @SerebiiNet
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