This is a very impressive dice rolling fighter with some well thought out modifiers on the dice - I especially love the steel face that makes the other side more likely to come up, having to think about the balance of your dice is really cool!
My only criticisms were that there should be a way to see what the modifiers will do to a die before you choose them - just some help text on both the choice screen, and on the slot (to remind players) would've gone a long way.
Great work!