Very well implemented game mechanics. Very fun for the deck-builder in me. I like the strategy of choosing between which cards to use and which to recycle. Makes combat more interesting, like a simplified version of chess. Looking forward to future updates!
Some notes follow:
The boss could use more minions or perhaps some special moves, as he's not much challenge. I wish there was a separate screen for the Upgrades, as it seems like its going to run out of space during my 3rd loop. Plus, it would just be more visually appealing. The taunting cards should actually play some kind of sound when used. There should be an indicator and/or a lockout method for trying to purchase/choose an upgrade you already have. As such, I actually bought TWO Steroids cards from the shop thinking they would stack with the other one I had already found, when sadly all I did was waste 200+ credits.
I have some issues with combat not resolving when using the Soldier's base shotgun cards (I think its called Buckshot?). It only started happening after my 2nd loop and also after I modified one of them to have 0 cost/Trash. Since then, about a third of the time I use a Buckshot (be in the 0 cost one or not) the card will do damage but then stops and never allows me to continue my turn. The red range indicators still appear so I suspect whatever event controls the ending of that card is bugged?