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Trainers,
Professor Willow has finally discovered Ditto! Trainers all over the world have
been reporting its appearance.
Ditto has been known to disguise itself as other Pokémon, so keep an eye out,
some Pokémon may actually be Ditto, and when you capture them, there’s a
chance that Ditto will reveal itself. If you do encounter a Pokémon that is
Ditto in disguise, the Pokémon in that specific encounter will also reveal
itself as Ditto for other Trainers.
Ditto is also a unique Pokémon when you interact with Gyms. When training or
battling at a Gym, Ditto will copy the appearance, types, and moves of the
first Pokémon it sees, and it will stay that way through the remainder of
those Gym battles.
The Pokémon GO team