Great concept, great story, great execution, I love a good fantasy coming to life game, and even more if it's in the form o a card game with gameplay that's actually fun, engaging and easy to understand, the story mode is incredible with all the paths you can't take and the actually interesting lore and side quests, this is definitely more than just a card game.
The pixel art is awesome but I do feel it lacks a bit of idle animations, which I find weird since the rest of the game is so masterfully crafted on the exception of the cards that use art/images from other games like league of legends and Marvel, I get the games is a mix of medias but this just doesn't look good, I hope it's just a place holder. Also check carefully the English translation.
For the rest, this game is by far the best card game I played here, is even more enjoyable than the likes of Hearthstone. You have a great concept in your hands, awesome job.