Then they somehow survive and their shenaniganery is remembered forever.
The gold old fuck around and find out. Some of my favorite memories pretty much all go:
“Yeah, you die.” “You didn’t even roll anything.” DM grabs a huge hand full of dice and throws them on the table. “Yeah, you die.”
To each their own, but I dislike that kind of DMing in my games. When I DM I try to collaboratively storytell. I make sure that I am aware of what kind of story my players want and make sure my players know what kind of story I want to tell, rather than punish them for stepping outside the bounds of my story.
I mean, that’s great, but when your player spits in the face of a God. Well. They fucked around, now they gonna find out.
Disclaimer: I only do stuff like this if the player is 100% in on the fun and I don’t present these types of opportunities lightly.
“But, I can roll my saving throw, right?” “No, you’re dead.”