There seems to be an issue with the card Spirit Ward: its seems to only use its effect (heal next direct attack instead of taking damage)whenever it feels like it.
Interesting game that is pretty fun to play, but it is absolutely ridiculous that all the booster packs and 90% of the decks require real money to access. I have hit a brick wall alarmingly early in the game apparently because I am unwilling to spend money on it to improve my deck.