Really cool game, here is some of my feedback after playing for a bit:
I think you could add a tutorial turn/fight to explain the mechanics of the game. The How to screen is long and there are no keywords or highlights to make some information stand out.
The music was a bit too low, I didn't even realized it until I started playing again.
I dont know if I got a bug, but in one of the fights, my turn was getting skipped when I was pressing the space bar to re roll the die. This would happen when I didnt lock any die before re-rolling. I checked the how to but I could not find any mechanic tied to this, so Im guessing it's indeed a bug.
I had some feedback regarding the drag and drop of the die in the tower itself, but I realized that this only happened because the screen resolution I was playing at. For some reason the screen resolution offsetted the mouse/place to drop the die. So the place did not match exactly with what I was seeing on screen.
But overall I really liked it and would like to see more of it for sure! :)