“ In this dungeon, the monsters will not be hostile unless you take something without permission. If you do take something, the monsters inside will consider it stealing and attack you.”
“ On a planet with an ammonia atmosphere, that is inhabited by intelligent aliens, the police carry oxygen spray, that has the same effect on that planet that pepper spray does here.”
“ In a miltaristic nation, the ownership of proper (improvised don't count) weapons and armor is mandatory for all citizens under penalty of inprisonment or death.”