Aetherverse

From the introduction:

Because this is a role-playing game (RPG), each player will be taking on the role of a character in the story. However, one person, whom this book shall refer to as the Game Master, is going to be in charge of running the world and all the other characters in it. This is not to say that the Game Master should be competing with the other players or trying to kill them because in a role-playing game, the Game Master, along with the other players, are there to tell a story. While this story might be something as simple as the tales of a few friends cleaning up a dungeon or doing errands for the local guards, it is still a story in which both the Game Master and the other players should have a part.