Man, the artwork of this game is fantastic! I love it! The game idea was also pretty cool and unique and interesting, but I felt like I had a little too little control over the outcome of my turns. Sure, the whole theme of this jam was "Roll of the Dice", but I still didn't really feel like there was a lot I could to when my die just didn't roll any armor spells 5 times in a row or so.
I think if you want to expand on this idea, you might need to find a way to give some more control to the player. I'm not really sure what's the best way to do that, but I feel like you can work something out. Also, some sort of power and difficulty progression, as well as more interesting enemy patterns would probably help to make the game feel a little less repetitive.
One more thing I really want to praise is that the UX design (apart from some hitbox issues) is pretty good. Hovering over symbols to see what they do works great and so does color-coding consumable spells. Kinda wish I'd still be able to see the enemy's intent when building my die, but that's a minor issue.