Interesting concept, especially for a defense game. I don't see what placing the dice has to do with anything, especially as the enemies seem to go right through them with ease. I was going to spend a lot of time digging tunnels and pits underneath to see what happens, but everything is super dark. Overall it's a very dark game, and with the graininess it's very difficult to see things from afar. That's part of the charm and presentation, sure.
You did well with the limited time. Great effort!