I'll start with the upsides.

 The artstyle and animation is beautiful and the sounds and soundtrack are pleasant. The characters are also all really cool and offer a very good deal of gameplay diversity (personally i'm in love with Hazel and Reva). The overall gameplay loop is fun and has good potential.

...but on the downsides.

The game is too difficult... there are a couple reasons for that. While there are alot of cards and while that's nice to see, there are too many cards that are just outright underpowered or bad for the player depending on what character they're playing as. You can avoid this by skipping cards but doing so doesn't compensate the player, so you either end up falling behind or have a deck that just doesn't work with itself and with no real meta progression outside of different loadouts you can get (good luck unlocking them in the first place) there's no way for players to mitigate the bad RNG. Another thing is the luck system, from what I understand and read online increasing luck also increases enemy difficulty. So the method for getting better cards more often also outright makes the game even harder yet you're still at the whim of RNG so ultimately... being lucky, isn't at all.

This game could be better off by not being so afraid of letting the player be OP earlier on and the idea of better meta progression options would likely be very satisfying, perhaps the ability to upgrade stats universally or unlock affects like an extra card or artifact every draw or even being able to start runs with certain artifacts.

Either way at the end of the day, as it is the game is more frustration than fun.