Originally Posted by syckrhythm
I don't get it... where do you see how many kills you've gotten?
From the main menu, go to Achievements and then scroll down to the 2000 kills achievement. There is a green bar at the bottom of the screen and it will slowly fill in black with every kill you get. There isn't any place to check the exact number, just follow the bar to know.
And yes it is CONFIRMED that you can only get these in ranked matches. Several of us tried it the other day.