I just fought a Ditto with my Ditto. They both just did a really weak attack on each other. Not sure what is was. Did very little damage and fight would have timed out if I didn't swap him out for something else and finished him off. And yes, it looks like the opponent Ditto's CP is about 50% of the pokemon you attack him with.
concerning Ditto
as sb already posted here, if u put ditto in a gym it copies the attacker. how do dittos stats/cp change in this case?
I used mine to attack and it behaved the same, though it's cp rose to about 51% of the defenders cp, don't know the underlying formula.
also, has sb of you caught a second ditto? and what happens if you fight ditto with ditto?
and what was the pokemon you caught initially
sry for the many questions, just raisin some ditto awareness
Answers
yeah that could be it! the arcanine I attacked was bout 2300cp and my ditto turned into a 1100ish one. assuming the arcanine was somewhere between lvl 25-30 and my ditto somwhere around 15 it would fit perfectly.
so the follow up question: should one lvl up a ditto? assuming you can catch more for candy