Overall polish and presentation is 5/5 audio, visual and UI all go together. For a 48Hour jam this is a great short look at a game.
The one thing that I found a bit hard to understand is the card collecting. I think I understood you could use monsters to destroy boxes, and get more cards, but sometimes that didn’t seem to work and once I ran out of cards I found myself running around until some popped up again. Maybe if the cards respawned after a while in your hand, and collecting cards would give you extras? (like you get 3 after having none for 3 turns, but only get 5 if you pick them up).
If you have time, would love to hear what you think of my game; https://itch.io/jam/gmtk-2019/rate/461074