Hi, I believe this is a very annoying issues since the recent patch.
Not sure how many people in the same situation as me ( as far as i search in google and seems the issue happen way back 1~2 years ago), I have been getting error and force close hearthstone, at random point of the game.
Not sure if there is anyone that willing to help out ? I just want to enjoy my battleground game without get irritate by random crash, especially when I get a good hand.
Also, I had been try out all the method that I can search in google, so please dont tell me to reinstall the game. 
What had i tested
- reinstall the game (duh)
- add hearthstone related folder to the exception list in my antivirus
- uninstall/disable my antivirus
- replace mono-2.0-bdwgc.dll file
- sfc/scannow until cmd say there is no error
I dont know what else should I do… please help…