I like the concept here and I hope you continue to build on it because I think it's really cool. The card upgrades are a little complicated but I think it becomes pretty plain pretty quick. It is sometimes hard to understand what is going on in a round, what effect you've had with your card, what effect the enemies are having on you, etc. Making the game easier to read will go a long way to making the game more tactical and fun. Also, and this might just be me, but I dont think I was setting enemies on fire with my card the way that it was supposed to. Also, and Im sure you know this but your music doesn't loop so after a few minutes its just sound effects. Anyways, I hope you keep working on this because I like it.