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A non-player character (NPC), or non-playable character, is any character in a game that is not controlled by a player.  The term originated in traditional tabletop role-playing games where it applies to characters controlled by the gamemaster or referee rather than by another player. In video games, this usually means a character controlled by the computer (instead of a player) that has a predetermined set of behaviors that potentially will impact gameplay, but will not necessarily be the product of true artificial intelligence.
In a traditional tabletop role-playing game such as Dungeons & Dragons , an NPC is a character portrayed by the gamemaster (GM).  While the player characters (PCs) form the narrative's protagonists, non-player characters can be thought of as the "supporting cast" or "extras" of a roleplaying narrative. Non-player characters populate the fictional world of the game, and can fill any role not occupied by a player character. Non-player characters might be allies, bystanders or competitors to the PCs. NPCs can also be traders that trade currency for things such as equipment or gear. NPCs thus vary in their level of detail. Some may be only a brief description ("You see a man in a corner of the tavern"), while others may have complete game statistics and backstories.
There is some debate about how much work a gamemaster should put into an important NPC's statistics; some players prefer to have every NPC completely defined with stats, skills, and gear, while others define only what is immediately necessary and fill in the rest as the game proceeds. There is also some debate regarding the importance of fully defined NPCs in any given role-playing game (RPG), but it is general consensus that the more "real" the NPCs feel, the more fun players will have interacting with them in character.
In some games and in some circumstances, a player who is without a player character can temporarily take control of an NPC. Reasons for this vary, but often arise from the player not maintaining a PC within the group and playing the NPC for a session or from the player's PC being unable to act for some time (for example, because the PC is injured or in another location). Although these characters are still designed and normally controlled by the gamemaster, when players are given the opportunity to temporarily control these non-player characters, it gives them another perspective on the plot of the game. Some systems, such as Nobilis , encourage this in their rules.
In less traditional RPGs, narrative control is less strictly separated between gamemaster and players. In this case, the line between PC and NPC can be vague.[ citation needed ]
Many game systems have rules for characters sustaining positive allies in the form of NPC followers; hired hands, or other dependant stature to the PC. Characters may sometimes help in the design, recruitment, or development of NPCs.
In the Champions game (and related games using the Hero System), a character may have a DNPC, or "dependant non-player character". This is a character controlled by the GM, but for which the player character is responsible in some way, and who may be put in harm's way by the PC's choices.
The term "non-player character" is also used in video games to describe entities not under the direct control of a player. The term carries a connotation that the character is not hostile towards players; hostile characters are referred to as enemies, mobs, or creeps.
NPC behavior in computer games is usually scripted and automatic, triggered by certain actions or dialogue with the player characters. In certain multi-player games ( Neverwinter Nights and Vampire: The Masquerade series, for example) a player that acts as the GM can "possess" both player and non-player characters, controlling their actions in order to further the storyline. More complex games, such as the aforementioned Neverwinter Nights, allow the player to customize the NPCs' behavior by modifying their default scripts or creating entirely new ones.
In some online games, such as massively multiplayer online role-playing games, NPCs may be entirely unscripted, and are essentially regular character avatars controlled by employees of the game company. These "non-players" are often distinguished from player characters by avatar appearance or other visual designation, and often serve as in-game support for new players. In other cases, these "live" NPCs are virtual actors, playing regular characters that drive a continuing storyline (as in Myst Online: Uru Live ).
In early and less advanced RPGs, NPCs only had monologue. Code directs the appearance of a dialogue box, floating text, cutscene, or other means of displaying the NPCs' speech or reaction to the player.[ citation needed ] NPC speeches of this kind are often designed to give an instant impression of the character of the speaker, providing character vignettes, but they may also advance the story or illuminate the world around the PC. Similar to this is the most common form of storytelling, non-branching dialogue, in which the means of displaying NPC speech are the same as above, but the player character or avatar responds to or initiates speech with NPCs. In addition to the purposes listed above, this enables development of the player character.
More advanced RPGs feature interactive dialogue, or branching dialogue (dialogue trees).  An example are the games produced by Black Isle Studios and White Wolf, Inc.; every one of their games is multiple-choice roleplaying. When talking to an NPC, the player is presented with a list of dialogue options, and may choose between them. Each choice may result in a different response from the NPC. These choices may affect the course of the game, as well as the conversation. At the least, they provide a reference point to the player of their character's relationship with the game world.
Ultima is an example of a game series that has advanced from non-branching ( Ultima III: Exodus and earlier) to branching dialogue (from Ultima IV: Quest of the Avatar and on). Other role-playing games with branching dialogues include Cosmic Soldier , Megami Tensei , Fire Emblem , Metal Max , Langrisser , SaGa , Ogre Battle , Chrono , Star Ocean , Sakura Wars , Mass Effect , Dragon Age , Radiant Historia , and several Dragon Quest and Final Fantasy games.
Certain video game genres revolve almost entirely around interactions with non-player characters, including visual novels such as Ace Attorney and dating sims such as Tokimeki Memorial , usually featuring complex branching dialogues and often presenting the player's possible responses word-for-word as the player character would say them. Games revolving around relationship-building, including visual novels, dating sims such as Tokimeki Memorial, and some role-playing games such as Persona , often give choices that have a different number of associated "mood points" that influence a player character's relationship and future conversations with a non-player character. These games often feature a day-night cycle with a time scheduling system that provides context and relevance to character interactions, allowing players to choose when and if to interact with certain characters, which in turn influences their responses during later conversations. 
On the Internet, NPC is often used as an insult to suggest that some people are unable to form thoughts or opinions of their own. Such people are often characterized as being similar to NPC Wojak, who is a grey-faced, expressionless internet meme.  
A gamemaster is a person who acts as an organizer, officiant for regarding rules, arbitrator, and moderator for a multiplayer role-playing game. They are more common in co-operative games in which players work together than in competitive games in which players oppose each other. The act performed by a gamemaster is sometimes referred to as "Gamemastering" or simply "GM-ing".
A live action role-playing game (LARP) is a form of role-playing game where the participants physically portray their characters. The players pursue goals within a fictional setting represented by real-world environments while interacting with each other in character. The outcome of player actions may be mediated by game rules or determined by consensus among players. Event arrangers called gamemasters decide the setting and rules to be used and facilitate play.
A player character is a fictional character in a video game or tabletop role-playing game whose actions are controlled by a player rather than the rules of the game. The characters that are not controlled by a player are called non-player characters (NPCs). The actions of non-player characters are typically handled by the game itself in video games, or according to rules followed by a gamemaster refereeing tabletop role-playing games. The player character functions as a fictional, alternate body for the player controlling the character.
A role-playing game is a game in which players assume the roles of characters in a fictional setting. Players take responsibility for acting out these roles within a narrative, either through literal acting or through a process of structured decision-making regarding character development. Actions taken within many games succeed or fail according to a formal system of rules and guidelines.
Neverwinter Nights is a third-person role-playing video game developed by BioWare. Interplay Entertainment was originally set to publish the game, but financial difficulties led to it being taken over by Infogrames, who released the game under their Atari range of titles. It was released for Microsoft Windows on June 18, 2002. BioWare later released a Linux client in June 2003, requiring a purchased copy of the game to play. MacSoft released a Mac OS X port in August 2003.
A role-playing video game, commonly referred to as a role-playing game (RPG) or computer role-playing game (CRPG), is a video game genre where the player controls the actions of a character immersed in some well-defined world, usually involving some form of character development by way of recording statistics. Many role-playing video games have origins in tabletop role-playing games and use much of the same terminology, settings and game mechanics. Other major similarities with pen-and-paper games include developed story-telling and narrative elements, player character development, complexity, as well as replay value and immersion. The electronic medium removes the necessity for a gamemaster and increases combat resolution speed. RPGs have evolved from simple text-based console-window games into visually rich 3D experiences.
The Avatar is the main player character and protagonist in the Ultima series of video games by Origin Systems. The character was first introduced as "The Stranger" in the 1981 role-playing video game Ultima I: The First Age of Darkness.
Dating sims, or romance simulation games, are video game subgenre of simulation games with romantic elements.
Ultima IV: Quest of the Avatar, first released in 1985 for the Apple II, is the fourth in the series of Ultima role-playing video games. It is the first in the "Age of Enlightenment" trilogy, shifting the series from the hack and slash, dungeon crawl gameplay of its "Age of Darkness" predecessors towards an ethically-nuanced, story-driven approach. Ultima IV has a much larger game world than its predecessors, with an overworld map sixteen times the size of Ultima III and puzzle-filled dungeon rooms to explore. Ultima IV further advances the franchise with dialog improvements, new means of travel and exploration, and world interactivity.
Ultima VI: The False Prophet, released by Origin Systems in 1990, is the sixth part in the role-playing video game series of Ultima. It is the third and final game in the "Age of Enlightenment" trilogy. Ultima VI sees the player return to Britannia, at war with a race of gargoyles from another land, struggling to stop a prophecy from ending their race. The player must help defend Britannia against these gargoyles, and ultimately discover the secrets about both lands and its peoples.
Ultima VII: The Black Gate is the seventh installment of the Ultima series of role-playing video games, released on April 16, 1992. In it the player returns as The Avatar, a would-be paragon of moral virtue who faces down many dangers and deceptions in order to cleanse the medieval fantasy world of Britannia of assorted plots and schemes, monster infestations, and the undermining of crown authority.
Ultima Underworld: The Stygian Abyss is a first-person role-playing video game developed by Blue Sky Productions and published by Origin Systems. Released in March 1992, the game is set in the fantasy world of the Ultima series. It takes place inside the Great Stygian Abyss: a large cave system that contains the remnants of a failed utopian civilization. The player assumes the role of the Avatar—the Ultima series's protagonist—and attempts to find and rescue a baron's kidnapped daughter.
Neverwinter Nights 2 is a role-playing video game developed by Obsidian Entertainment and published by Atari Interactive. It is the sequel to BioWare's Neverwinter Nights, based on the Dungeons & Dragons fantasy tabletop role-playing game. Neverwinter Nights 2 utilizes an adaptation of the Dungeons & Dragons 3.5 edition rules. Players create player characters to represent themselves in the game, using the same character creation rules as found in the Dungeons & Dragons game. They may gain the assistance of additional party members, and they eventually acquire a keep that can be used as a base of operations. Neverwinter Nights 2 is set in the Forgotten Realms campaign setting—in and around the city of Neverwinter. The story is mostly unrelated to Neverwinter Nights and follows the journey of an orphaned adventurer investigating a group of mysterious artifacts known as "silver shards" and their connection to an ancient, evil spirit known as the King of Shadows.
Ultima Underworld II: Labyrinth of Worlds is a 1993 first-person role-playing video game developed by LookingGlass Technologies and published by Origin Systems. As the sequel to Ultima Underworld: The Stygian Abyss, the game is set in the Ultima fantasy universe. Players assume the role of the Avatar—the protagonist of the Ultima series—and adventure through multiple dimensions while seeking to prevent the evil Guardian from achieving world domination. Progression is largely nonlinear and the game allows for emergent gameplay.
Role-playing games (RPGs) have developed specialized terminology. This includes both terminology used within RPGs to describe in-game concepts and terminology used to describe RPGs. Role-playing games also have specialized slang and jargon associated with them.
Neverwinter Nights 2: Mask of the Betrayer is a role-playing video game developed by Obsidian Entertainment and published by Atari Interactive. It is an expansion pack for Neverwinter Nights 2. It was released in Autumn 2007 for the PC in North America, Europe, and Australia. Like the first game, Mask of the Betrayer is set in the Forgotten Realms campaign setting of the fantasy tabletop role-playing game Dungeons & Dragons and employs the 3.5 edition rules.
A dialogue tree, or conversation tree, is a gameplay mechanic that is used throughout many adventure games and role-playing video games. When interacting with a non-player character, the player is given a choice of what to say and makes subsequent choices until the conversation ends. Certain video game genres, such as visual novels and dating sims, revolve almost entirely around these character interactions and branching dialogues.
Neverwinter Nights 2: Mysteries of Westgate (NWN2:MoW) is an expansion pack for the role-playing video game Neverwinter Nights 2. It was developed by Ossian Studios and published by Atari Interactive on April 29, 2009. The player creates a character and controls it, along with a group of three pre-designed companions, journeying through the game world. The gameplay is very similar to that of the base game. Mysteries of Westgate also includes new monsters, music, and other tools, which can be used by players to create their own Neverwinter Nights 2 levels.
Neverwinter Nights is a series of video games developed by BioWare and Obsidian Entertainment, based on the Forgotten Realms campaign setting of the Dungeons & Dragons role-playing game. Aside from also being set in the Dungeons & Dragons world and around its city Neverwinter, it is unrelated to both the 1991 Neverwinter Nights online game and the 2013 online game called Neverwinter.
Western role-playing video games are role-playing video games developed in the Western world, including The Americas and Europe. They originated on mainframe university computer systems in the 1970s, were later popularized by titles such as Ultima and Wizardry in the early- to mid-1980s, and continue to be produced for modern home computer and video game console systems. The genre's "Golden Age" occurred in the mid- to late-1980s, and its popularity suffered a downturn in the mid-1990s as developers struggled to keep up with changing fashion, hardware evolution and increasing development costs. A later series of isometric role-playing games, published by Interplay Productions and Blizzard Entertainment, was developed over a longer time period and set new standards of production quality.