I accidentally pressed N and the level was restarted and I had 4 dices :D I think I found something hidden <_<
Curious story telling here :D I think you could show picking a dice more clear to a player, highlight a chosen dice. Chosen and spent dices looks similar for now. Also, what I miss is that there is no option to choose another dice, so I have to choose another opponent to cast this dice on.
Overall, it's a nice idea, I would wait for your updates!