This game felt very finished and clean already.
There's a lot going on, but it's not too bad to keep up with. There's some arbitrary concepts like caltrops and defending cards, but you implemented tooltips to go along side things which I think is nice. Having to click instead of just hovering over stuff is kind of weird I guess but at least it's there.
I do feel like the AI can be exceptionally punishing. Like they really just completely eat the entire board sometimes, but they don't use their SP. It's kind of weird. I am not sure if it's intentional but yeah I got my ass kicked.
I think in the beginning I was learning how to check tooltips and I clicked the enemy's attack card and it attacked me. Not sure if coincidence or what, but it's kind of weird to show the enemy's attack cards in the exact same place as your own, even though it's their turn.
Overall very nice, well put together demo. I would like to see maybe a bit more interesting base archetypes instead of the usual 'do 3 damage... and then draw a card' or whatever. Maybe advanced characters that you unlock after some time with the game.