This Pokemon is one that can only be obtained through giving a Ditto "challenge mail". "Challenge mail" was once in a monthly parcel in December 2011, but can now be bought with Donation Points. It is based on the internet meme "Challenge Accepted". It's nature is a special nature that can not be found normally on other Pokemon, "Challenge Accepted". This Pokemon is the same as a Ditto, but bears the face of the "Challenge Accepted" meme.Giving Challenge Mail to a Ditto will turn it into a Challenge Ditto, with a 10% chance to turn it into a shiny varient. Giving Challenge Mail to a shiny Ditto will always result in a shiny Challenge Ditto. The Challenge Mail is deleted after use.
Challenge Ditto can not be bred, as it functions the same as a normal Ditto. However, it's nature can be bred to other pokemon while holding an Everstone (5% chance) or a Secret Potion (10% chance).