Fun game, and awesome interpretation of the theme. I don't think I've played any other games that used explicit fuel as the thing that everything costs some of. But now that I've seen it it seems obvious. Those are the best kinds of ideas.
But yeah, pretty fun little mining/resource management game loop. The audio really helps sell the "big mech crunching through rock" vibe
Very punishing when you mess up, but I think it works well for this style of game.
Great job!