This is a very cool idea! At first I couldn't figure out how to shoot - in fact I didn't know you could at all, but once I did (space to shoot if anyone reading this is unsure), it became a delightful grid-based bullet-hell, which in itself is a very interesting concept, but the different firetypes for different face values made gameplay very interesting. I felt I didn't have a terrible amount of control over the firing pattern. Perhaps showing what face value would come up if you rolled in each direction would help? Like a sort of half opacity clone in front of each of the player's cardinal directions which showed the value?
While the game isn't terribly polished (except for the dice rolling animation which was way more satisfying than it should have been), this is a really fun game!