Very good game to be made in such a short time, I liked the art a lot and consistant style of the visuals, everything felt smooth and bug free. The game made me need to think of how to manage the cards and I changed how many of good/bad ones I worked with as I went on. Enjoyed it a lot and played till the end. Music was nice, not too intrusive for background music. Difficulty scaling seemed about right.
Only note I would have is that even after reading the instrustions at the bottom, I still dragged things around for a minute or 2 trying to undertand how to hurt the enemies using the Key up top corner but once I got that, the rest made sense. So I would suggest slightly different/more to the tutorial instructions.