pretty sure this idea has bounced around my skull for literally years now: getting isekai'd into a world that's so magical that physics to some degree just doesn't exist as we know it, and the protagonist is so violently mundane that they have an aura of normality where magic simply cannot exist and physics works as we're used to.
And depending on which way you want to take it they can either just have that as a passive thing that has to be worked around, or they can have some level of active control that they can improve over time, so they can reign it in to be healed and extend it to even cause inherently magical creatures to just kinda.. get erased from existence..
nope, i'm the type of person who can write up a silmarillion about things that tickle my brain, but ask me to write an actual story and i'm going to throw the pen at you.