I was playing my rainbowesque nyphomania(notacopyomg) deck against AI3, cos it's awesome. I was against the FFQ ai3 and was pretty much antimattering everything in the field. In time I got dark nymphs as well and um... well a lot of things started going odd about the damage done to the ai. The damage the fireflies did weren't really shown as damage,(the damage was shown as a simple number without + and -, only +), however some damage was actually dealt. The damage, unfortunately, did not match the creature attacks(firefly atk 3, damage done 2).
And a screenshot what'll be a lot better than my explanation:
