Congrats on your first Game Jam submission. I hope it was as rewarding for you as my first time was for me.
Let me say, good job for a first Jam. You implemented a simple turn based combat system and stat system (which can be quite complex under the hood), animations, UI popups, upgrades, and art. For me, it was bug-free! Shiny mode was also a fun addition as a trade-off for more power <3
Now my 2cents of constructive critique. I will echo what others have said - try to focus a bit more on the Theme and Player experience.
1. Theme: The dice rolls could have been replaced with a simple attack animation without really changing the game experience. This is a sign that the Theme is not being utilised to its potential.
2. Player Experience: I love traditional turn based battle systems so I am probably from this games key audience. I find the fun of these systems is in player strategic options. Apart from picking upgrades, I had no agency to influence the battle. I still played through to the end, but this was a let down for me. Even a simple Scissors-Paper-Rock (e.g. Physical > Magic > Counter> Physical) could have improved the experience substantially.
Good luck with your next Jam.