This is a neat concept for a game and I think it could go somewhere. I like the card-ness of it. I think you could make a really unique roguelike/lite out of this if you added a deck building aspect. "Here's your starter deck (i.e. three boots, a machete, and a medikit) and you've got 20 gold to buy the rest of your supplies." Then after each level you buy more gear to tackle the next level.
I also really enjoyed the multi-card boss at the end. I was not expecting that, and it shows out-of-the-box thinking. Good job!