How to catch Ditto in Pokémon Go in 2018Not only has Ditto learned to hide as Ghastly, Whismur, and Gulpin, catching a Ditto is one of the stage 5 tasks required for finding Mew!
Ditto is a Pokémon who can transform — essentially take on the appearance and attributes of other Pokémon. Although missing from the original release of Pokémon Go Gen 1, Ditto eventually found its way out into the world, hiding as Pidgy, Ratatta, Zubat, and Magikarp. With Gen 2, Ditto also learned to hide as Sentra, Yanma, and Hoothoot, and Gen 3, as Zigzagoon and Taillow. Then, when Shiny Magikarp appeared, Ditto Magikarp disappeared. Now, just as Ditto has become a prerequisite for finding the mythical Mew, Ditto has added Ghastly, Whismur, and Gulpin to its repertoire as well.
So, come out, come out, wherever you are. It's time to play hunt and go catch!
Update: Pokémon Go Kanto Event skews potential Dittos
Pokémon Go is currently running a Kanto-themed event with increased Gen 1 spawn...
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How to catch Ditto in Pokémon Go in 2018