I chose Rakanishu and his Burning Wit after beating first boss my next opponent was Marei Loom but not before I got “Hagitha’s Embrace as a passive”. The fight started out normally enough some of cards in my hand got buffed a few times and even some of those same cards got sent back into my deck, however at some point during the battle when it was my turn my deck refused to draw my next card and basically keep me trapped there until I was forced to concede. I believe what happened was my deck refused to draw a card because it had trouble identifying the next card, since it was most likely a buffed minion in stats and/or cost. If you can fix the issue that would no doubt be appreciated.
This is a known issue. See for example:
If you encounter this issue again, you can force-quit Hearthstone (Alt+F4 in Windows) and restart it right away to return to the game in progress and clear the invisible card (though future draws might still have the same problem).