Player's Handbook > Introduction > How to Play > 1. The DM describes the environment.
It's literally the first rule. I enthusiastically support changing the rules, but if you change one of the most fundamental rules of the game without explaining it to your players in advance, it is absolutely your fault if they don't understand.
Player's Handbook > Introduction > How to Play > 1. The DM describes the environment.
It's literally the first rule. I enthusiastically support changing the rules, but if you change one of the most fundamental rules of the game without explaining it to your players in advance, it is absolutely your fault if they don't understand.