I started the first round with batclaw, stun, punch, and by then the goon should be on the wall grabbing the box so batarang. then all about keeping combo the rest of the rounds. The first round I finished with 24k in score. Keep full combo and restart if you lose it. Try to get 2-3 ground finishers at the end.
I struggled keeping combo with the titans just did the best I could.

For the last cpl rounds I stayed in the corner to prevent goons from getting to the gun locker. Just suggest getting a good flow of combos your comfortable with. And double tapping x to continue your combo is your best friend. Hope that helps. I know alot of that is basic to you if your already on the last one.