I'm most certain you mean metaphorically, otherwise that wish is already bad as it gets, lol! Anyway, you wind up toning it down a notch and lose your "shithead of the year" awards and fade away into obscurity until everyone forgets even the utterance of your name - you're shitheadness was who you were and without it, you're nobody

I wish I could quite literally melt whatever I looked at (at will of my choosing) in seconds.