Unown/Regional Events, Pokémon GO Wiki

In general, Unown is extremely rare all around the world, but there are certain regional events, such as Pokémon GO Safari Zone, during which spawnrate of certain Unown forms were higher. These more often spawning forms of Unown spell a word related to the event. This happened already during following events: Pokémon GO - Unown Events page, on Serebii.net

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