Every time Frozen is played, it is reduced by 1 and the rest of the card is skipped. So 'Frozen 2' card will have to cycle through the deck 2 times before it works. When reaching zero, Frozen disappears. I will improve effect description to make it more clear.
The previous bug was due to the fact that I compared "frozen === 0" rather than "frozen <= 0".
>I don't think having to play it another time would be particularly hard
Ok, changed it to (difficulty + 2)