The Kanto tour of introduced a Shiny variant of the Normal-type Ditto that is extremely difficult to find and catch. One of the Special Research Tasks from this tour allowed you to find shiny versions of all the original 151 Pokémon from Generation 1. Creatures from the Kanto region still have their Shiny forms now, but they are some of the rarest Pokémon to obtain in the game.
Some Pokémon you encounter could be a disguised Ditto in since the creature has the power to transform. During the tour, you only needed to acquire the Kanto Tour Pass to receive a free Shiny Ditto at the end of the challenge. However, you now have to deliberately hunt down Pokémon that Ditto could have changed into while you also try to collect a Shiny variant.
You have to understand which Pokémon Ditto could be before you can find a Shiny version of the blue putty. Ditto's disguises change every month in, so you have to stay up to date on each creature that may be a transformed Ditto. As of this time of writing, Ditto could be any of these Pokémon:
Keep in mind that just because Ditto is a Normal-type Pokémon, it can transform into a creature of any other type. For example, Ditto has an equal chance to be a Pidgey or Klink in when you encounter them.
Any of the Pokémon listed have a chance of being a Shiny version of Ditto once you get past their disguise. Unfortunately, there is only a slim 1 in 64 chance to get a Shiny Ditto from any encounter involving the creatures mentioned in. This may be one of the hardest Pokémon to find in the entire game, so you may need to seriously grind to add it to your collection.
Continue trying to catch the right Pokémon in the wild whenever you can in large numbers. Casting a wide net will give you the best chance to hit the right odds and get lucky at least once if you didn't participate in the Kanto Tour event. Those who try hard enough are likely to eventually find and catch a Shiny Ditto in and brag to their friends about their extraordinary effort to
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