Damn, every time I think I'm original or clever today, someone beats me to it.
I was just thinking of "demon core on a warhammer/shield/trebuchet (not a catapult because that's for plebs)"
Small point of pedantry, that is a flail, not a mace. A mace is mounted directly onto a handle, flails have the flexible material between the weight and the handle.
You're not alone, you're together through time with so many others past and future. None of us are going to put up with repeatedly subpar copper ever again.
That would be a Jedi lightsaber. I can't remember which YT channel calculated the amount of energy in those little bastards but I think it was about a small nuclear recator