<P> Arrangers called gamemasters (GMs) determine the rules and setting of a LARP, and may also influence an event and act as referees while it is taking place . The GMs may also do the logistical work, or there may be other arrangers who handle details such as advertising the event, booking a venue, and financial management . Unlike the GM in a tabletop role - playing game, a LARP GM seldom has an overview of everything that is happening during play because numerous participants may be interacting at once . For this reason, a LARP GM's role is often less concerned with tightly maintaining a narrative or directly entertaining the players, and more with arranging the structure of the LARP before play begins and facilitating the players and crew to maintain the fictional environment during play . </P> <P> Participants sometimes known as the crew may help the GMs to set up and maintain the environment of the LARP during play by acting as stagehands or playing non-player characters (NPCs) who fill out the setting . Crew typically receive more information about the setting and more direction from the GMs than players do . In a tabletop role - playing game, a GM usually plays all the NPCs, whereas in a LARP, each NPC is typically played by a separate crew member . Sometimes players are asked to play NPCs for periods of an event . </P> <P> Much of play consists of interactions between characters . Some LARP scenarios primarily feature interaction between PCs . Other scenarios focus on interaction between PCs and aspects of the setting, including NPCs, that are under the direction of the GMs . </P> <P> LARP does not have a single point of origin, but was invented independently by groups in North America, Europe, and Australia . These groups shared an experience with genre fiction or tabletop role - playing games, and a desire to physically experience such settings . In addition to tabletop role - playing, LARP is rooted in childhood games of make believe, play fighting, costume parties, roleplay simulations, Commedia dell'arte, improvisational theatre, psychodrama, military simulations, and historical reenactment groups such as the Society for Creative Anachronism . In a contribution to a volume focusing on play and cities in Springer's Gaming Media and Social Effects series, Eddie Duggan (2017) provides an overview of pervasive games, and discusses characteristics in ARGs, LARPs, RPGs, Assassination Games and other games where the notion of the "magic circle" as elaborated by Salen and Zimmerman is confounded . </P>

What is it called when you dress up and fight