The term Dungeon Master (DM), Game Master (GM), and Narrator are often used interchangeably. These terms all describe the person who runs the game. A GM is a person who, in and RPG, is responsible for everything in the game that is not the players. If you have played a videogame before they are basically everything in it that is not you. This means they are responsible for the plot, enemies, system management, and non-player characters. Whenever there is a rules dispute the GM is the one who makes the final call. Being a GM is often considered the most difficult role in an RPG and finding a good one can be hard. Outside of running the game it is also their responsibility to keep the table focused on the game and to handle disputes that come out of character.
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