I know people have done all of the combo challenges, etc. I have done this one many times, with all 7 hits getting counted again and again, and it won't give me a success response.
Oh yes! This one was tough as hell IMO. It took me some hours before I could perform this combo.
Here's my advice:
First, do not try to perform the combo on a wall. It is clearly a mid screen combo. Second, after you juggle the opponent (backwards+X) move a little bit forward and try to hit him as soon as possible.
And that's pretty much it. Just try and try and try and try. Good luck and merry Christmas!
I've done much harder ones than this. As I've said, I have done it many, many times, but for some reason, the game won't give it to me. I usually do move forward a bit after the bounce, but no go. I've even shown the wife several times and we just don't get what is wrong because I get all 7 hits in, with the last kick ending the juggle.
Thats really strange... maybe you should choose a different character as your opponent? Darkseid or Batman for instance (works better than others... for some reason) Edit: BTW: Got the same problem with one of Cap. Marvels Combos. Everything was fine, every hit connected and so on but the "success" shit didn't pop up. One day it worked just fine... and I still don't know why. Maybe you have to hit one special frame ... nah, idk.