Drawn cards are invisible. this happened after playing Dr. Morrigan
The invisible cards drawn issue is well known and affects all (?) effects which shuffle cards in opponent’s deck. See:
If you encounter again an issue which prevents you from playing, you can force-quit Hearthstone (Alt+F4 in Windows) and restart it right away to return to the game in progress. This workaround should clear the invisible cards from effects like this (though future draws might still have the same problem), until a proper fix is implemented by Blizzard.
Okay thanks for the reply /cheers!
Same problem with the app, and psicquescream
Had the invisible cards + unable to play the other cards + greyed out End Turn button without using Dr Morrigan. After 5 turns my next drawn cards were visible and the end turn button was clickable, but the cards from the 5 intermediate turn draws were still invisible.