Decently fun for the state it's at. I like the art direction. I assume it's not finished yet so you probably already know about most of these issues and missing features, but I'll put the things I noticed just in case there's anything you didn't realize:
The healing on the old whiskey doesn't work.
The red cards that list their cost as 0 actually cost 1.
Ferocity has no effect as far as I can tell, but in the game's current state that might be a positive to the balance.
Enemies are inconsistent between displaying what they're about to do and what they just did (notable with bleed effects being applied the round before the enemies say "bleed 3"). Related, block and dodge being listed together with their actions makes it confusing of whether they're planning to add block/dodge for their next turn, or whether they currently have that much block/dodge.
Taking another card of the same type sometimes makes the original card more powerful, inconsistent with whether that's instead of or in tandem with getting another copy of the card (ex. adds 1 weak will become adds 2 weak). It's good to have both upgrades and card additions, but some specification of which will actually happen is needed.
Map defaults to being scrolled all the way to the bottom, even if you're at higher rooms that aren't visible from the bottom of the map.
Boss's hitbox is off; you need to drag the card to the space between you and the boss to target it.
Assuming weak is supposed to weaken enemy attacks, it doesn't actually work. (I assume it's weakening their attacks and not weakening them against your attacks because then what would vulnerable mean?).
No way to restart the game on win or loss (besides reloading the page)
Enemies adding strength seems to do damage sometimes? And a lot of it too. I would assume strength is supposed to be an attack buff but the damage happens when there's no attack listed for the turn.
The card that replicates the previous card could be worded more clearly IMO; I at first thought that playing it repeated the previous action, rather than creating a copy of the previously played card, which is a HUGE power difference.
Not an issue per-se, but some animations (even simple ones like glides and shakes on the still sprites) would go a long way IMO. Having a tutorial or legend explaining what different effects/keywords do/mean would be nice. And as it stands, the branching paths of the map aren't doing anything functional to affect the game, as they're always the same type of room across a horizontal line and you get no hints towards the difference between them (if there even is one). In this kind of game I always appreciate a way to cull cards from your deck (for a price, whether that just be missing out on another option, or some other cost).
Hopefully this isn't too harsh! I just wanted to make sure that no problems slip through the cracks. I think this game has a lot of potential.