The game is fun, simple yet deep, visually appealing and challenging. The only problem I had was the enemies. Most of the enemies were just simple attack/block enemies, with just numbers and slots going up. So the challenge was not how to deal with the enemy design, but with the numbers.
Another thing was the hand. You always had the same cards in your hand and that's while not bad, made the game easier and less strategic.
Overall the game was fun and nicely executed. Good job!