i aslo have some recomendations but not ones to improuve the game just some ideas for cards and also one hero idea
- a parry card that blocks the next incoming attack but does no damage this might be a bit op so you could give it a long cooldown
-sword dash just a casual sword dash thats 2 tiles long and peirces enemies. (you can pick the amount of damage)
- if this is not already a card then i suggest a cross bow that deals 2 damage has a long reload and fires 1 less tile then a bow
Hero idea: i would suggest a monk or a archer / crossbow man the archer would start with two arrows and 5hp and the monk would have a bo staff and some sort of heal spell that heals 1hp and takes forever to reload (you can put any other spell for him too, just heal sounds like a monk thing).
Anyone feel free to reply if you have more ideas.