Niantic has officially confirmed the release of the rare Ditto Pokemon into the game via an update post and video. In the video you see what would happens when you catch a normal Pokemon only to get the special music and see Ditto pop up! As the social media account have shown Ditto has been being caught by Trainers across the globe, but the post shares some neat details on Ditto especially where Gyms are concerned.
Ditto can be used in Gyms to train or battle Ditto will copy both the appearance and attacks of the first Pokemon it encounters. This has some intereresting ramifications for battle. Lets say I start my battle with a Pidgey then beat Ditto with the weak attacks then switch to a stronger more powerful one? Guess further training and battling will show what happens when Ditto is being used or battle/trained against.
See the video: