Ok so, first off, I think the concept is very good, and the art and music really help with getting into the flow.
Just a couple of critiques from a design perspective:
- Firstly, the attack and block mechanics: There's little to no incentive to not use attack and block cards right away besides some specific scenarios where you have to wait for a slightly better hand combinations. This creates very little interesting situations (dynamics). A suggestion I have is making it so after combat, attack and block are reset to 0, so the player has to choose whether they want to "waste" that extra resources to ensure they won't be taking damage, or if they want to risk it and slowly deteriorate their health to not lose resources in the long run. This would also make health and block two resources which are situationally one better than the other, instead of having block as a straight up better version of health. These two conondrums combined would help players develop their own heuristics, seeing the game as a form of personal expression and getting more emotionally attached in the process.
- Secondly, the hand combinations: There's a clear inspiration from balatro, which is not necessarily a bad thing, but I think it clashes with the Solitaire aesthetic you were going for and makes this compact experience more complicated than it needs to be.
Then I think a couple of tweaks could be made to ensure a generated "floor" is always winnable, and less columns to force the player into tighter spots. But that's more of a matter of balance rather than design so it's up to preference, and can be sorted out later into the pipeline.