Hey Sstrandberg, Dungeon Card Game Dev here.
I loved this. It was so damn good. Amazing how simple dominion turns into a cool single player card game. I hope you want some criticism...
The UI could use some work to make it more intuitive. The game ramps up fast, which is great, don't slow it down. I don't like how attack cards are and aren't action cards. I kinda want the shop to be a bit more random(I know its early days for your development), but having a few piles of cards and whenever you buy a card from that pile it reveals a new type of card. But that breaks away from dominion and crafting your engine feels nice.
Hmmm, beating it took me 8+ attempts and I am a dominion 'veteran'. So fantastic job on the difficulty.
I can see this being a really great phone app to piss away 10 minutes. GJGJGJGJGJGJGJGJGJ