Is the rat the final boss or did my game just crashed?
It's a nice concept and I'd really love to play if it was more polished. I suppose most issues and drawbacks were described in the comments before me, yet I still want to point out game's unintuitiveness - e.g. I couldn't understand when does the attack during the battle starts, why I've dealt like 6 damage if I've chosen a card with value of 2, etc. Use of cards for damage/healing is obvious, but battle system in general is quite confusing.
Overall, it's a nice small game. Unfortunately I can not say much :(
If you have a will, I'd be glad if you rated my submission.