What is the chance of getting a shiny HA Ditto in a Friend Safari?

Question

When I was GTS Trading in UM, I found a shiny, Imposter Ditto. Once I traded for it, I saw it's player data and it said that the Ditto traveled from the Kalos region. I knew it was very rare and can only be found in the Friend Safari, so how rare are shiny hidden ability Ditto in the Friend Safari?

Answer 1

In order to get Pokemon with a HA in the Friend Safari, you need to have all 3 Pokemon slots unlocked by you and your friend being online at the same time (both having beaten the Elite Four). Seems that the exact chance of finding a HA is unknown, according to everywhere I've looked, everyone says something different. Finding a shiny in the Friend Safari is a 1/512 rate.

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Comments

I’ve found 7 shinys so far all in the safari zone, it’s not that rare

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Do you have to have all 3 Pokémon registered In order to get that 1/512 shiny rate as well?