Rule 8.1, paraphrased: “play the ball as it lies”
Many years ago I was playing golf on Cape Cod—it was a very windy day and my hooked drive took off into a pasture and hit a cow.
It dropped right under the cow, and the cow did not want to move to let me hit the ball.
I had no clue what the rule-book said about that....I called it an “unplayable lie”....
;-)