The game is good, but the card acquisition system and the aggressive mobile gaming monetization model are complete ass. Things have improved a bit since its first few months, but it's not enough. Not to mention the bots you find (especially in lower ranks), it's rare to face a real player. They do this so that you win more often and are compelled to keep playing instead of giving up and uninstalling the game. It's predatory and quite unethical, even if the gameplay is unique.
I tried to get into it again but I've given up.