Having the option to use Vigor in some spells

Okay, I tested that, and while physical damage done with attack is fine (more consistent) (thanks Madsuir!), the pummel equivalent is still...peculiar. It does consistent damage (110-114), yet, at times, it does a jump at 148, as if it were a critical hit. This can happen in the same battle where the other attack is and has done 110ish.
It's really weird, almost if there was a 25% boost of a magic critical hit of some sort. Maybe Vigor is tied to the possiblity of a critical hit, so when the physical damage bit is ticked, it causes it to randomly perform a critical? I don't know.