Well polished! The pixelated cards are very well done. I can think of some polish tweaks that would be nice, but to be honest... I'm not a fan of the gameplay itself. I like when I'm able to make choices, so even adding a little bit of variety in the mechanics would help - such as having to choose between two different cards to play, or allowing us the ability to add bonuses to our card to help us win. But I do like the cohesiveness of your theme, your visuals, and the sound design.