Great art and interesting gameplay! Made it to the gloom door after a few runs. I really had some great time with it.
About the game balance, I think Rolling Death is way too op. I got two in my last run and the third boss were totally crushed since every hit from those cards would be fatal after some 2x damage upgrades. Not to mention it is a 0-cost card!
A bug that I encountered: I had two Psychosis in my hand and I played one of them. I died because of the self damage and that's fine. However, there are still two in my hand after I was revived.
Great game anyway. Keep it up!