I think the battles themselves are very fun, but the loot could use some work. It feels like there is too much given out after each battle to the point that it’s a bit overwhelming. It also does not help that it is hard to tell the difference between all of the different weapon types.
I think giving out less loot after each battle, but having that loot be more unique in its function would improve the progression a lot. Maybe some of the weapons deal more damage, while others deal less damage but have helpful secondary effects. It could also help to have more info on each item when you hover over it (something to the effect of deals x damage rather than just saying deals a small amount of damage).
The visuals and sound design are both very good where they are at, though as some people have mentioned, simplifying the UI some wouldn’t hurt, there’s a lot on the screen at the same time, especially in the inventory screen.
I do really like the deckbuilding aspect to it and think with some more polish in how loot is handled this could become something very good.