A good game, but a bit buggy in places. The main two that I have spotted:
1) Cards moving off the top of the screen as they continue to attack (which as a pain if you can't see the creatures stats)
2) In the league mode you are always given a defeat in the final match, even if you win comfortably. I've played through the league twice now, and the first time I was ahead far enough that the incorrect loss didn't effect my position, but the second time it cost me top spot.
Otherwise it plays well, even if it is very difficult in places. Some of the campaign matches I can't get anywhere close to beating.