I love Yui so much! I like that you went out of the way to attempt to create an original character for this; it shows an ambition that I like seeing in Jams like this.
As for the game itself, not having to worry about dying was nice! A lot of the TH1-inspired entries in this jam are particularly merciless with the yin-yang orb, so it was nice just to chill and focus on hitting things. I played on controller and unfortunately, it felt fairly unintuitive-- but I slid tackled my way to victory, so it all worked out in the end.
There's also not a lot of polish in general, which is understandable given a three-day cycle. What matters is that the essentials (the character sprite, the orb and the cards) all feel very authentic to their inspiration. I also love the storytelling device you have here. It's very cute and I think is good to have for this style of game. Nice job!