Extremely unbalanced and completely unplayable once you get to a high level due to how blatantly pay to win it gets. It sucks that a game of this size and popularity is so hardcore pay to win. It's made so extremely difficult and time consuming to collect enough cards and coins in order to max out and level up your cards without spending loads of money. There are many instances where you will be completely helpless no matter what you do against players with overpowered, broken, max level cards.