Gamemaster
One common feature of many RPGs is the role of gamemaster, a participant who has special duties to present the fictional setting, arbitrate the results of character actions, and maintain the narrative flow. In tabletop and live action RPGs the GM performs these duties in person. In video RPGs many of the functions of a GM are fulfilled by the game engine, however some multi-player video RPGs also allow for a participant to take on a GM role through a visual interface called a GM toolkit, albeit with abilities limited by the available technology.
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