I would have preferred the opening dialogue sequence to be a bit quicker.
The UI where you choose your power-ups if visually confusing. The artwork is gorgeous but the colorful buttons you must press on don't really stand out are UI elements, they just look like part of the background.
The use of the theme is very very cool. I like that idea a lot and even though the card builder menu was a bit confusing, its still a really cool gameplay idea.
Obviously, the artwork is amazing. Very nicely detailed characters and environments. The character designs are, also, very nice.
The bosses are quite fun to versus. I feel the difficulty is justifiable in the sense you can try and utilize more cards if you'd like.
The music is very nice. I like the Dark Souls style choir and off-sounding strings mixed with the rock elements; it makes for an interesting combination.
Overall, a very good submission.