I like the slay-the-spire esque deckbuilding aspect of upgrading individual dice, I think my main issue is that the gameply itself feels uninteresting. There's no reason not for me to just always take the highest roll. I'm not sure the best way to solve this, but maybe having to assign 2 dice per character per round (one attack on defense) rather than alternating, or having some sort of special effect dice could be good. I'd also nitpick that the player feedback was a little rough around the edges, some more animation or UI would have been good, but I understand that the timeframe probably made that hard to do.
Overall though I had fun and the art looks great!