Once your oppontent has triggered their top heavy attack, as the Shaolin, Parrying is one of your best options.
Parrying is one of the defensive plays in your arsenal and gives a frame advantage if succesful (you get a little extra time to attack your opponent before they recover).
To pull this off, press heavy attack in the same direction your opponent is attacking from.
You have to time it right, so your reactions need to be on point.
If you are getting the hang of your opponent and their combos, you might be able to anticipate their move, or interupt a combo you know is coming!
If you are looking for tactics, or tips on certain heroes, or gameplay strategy in general, there are plenty of resources online!