Mythical Special Research - Shiny Celebi .

When players logged into Pokémon GO during the period of December 14, 2020 to February 28, 2021, they gain access to the special research that yields a Shiny Celebi upon completion. Players do not need to complete the research within the period.

The special research was available to players to promote the then upcoming movie in Japan, Pokémon M23: Coco (the movie has the name changed to Secret of the Jungle internationally).

For this file to be transferable across games without any stats oddities, you cannot modify any immutable values.
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