This was a really good execution! I gave it like 4 attempts and I'm only stopping because I have to go. I loved how I had to make strategic choices on when I decide to give up on a minion and go to the next one. The random cards system was really fun and provided a lot of interesting decisions and choices that kept me on my toes. Do I risk using 1 mana to draw two cards and hope for a replenish mana card, or do I maximize damage and just let this minion die?
My only critique was a lack of tutorial, either on the page or in the game. I know that tutorials are hard to implement in 48 hours, no fault there, but an explanation on the game page would've helped me out in the beginning. At first I thought I was the knight guy, and was confused on what the HUD elements meant or how to apply damage and blocks to people. But once I figured it out, it was a fun experience!
Great job!