Unlockable character

A player character (also known as playable character and abbreviated to PC) is a fictional character in a role-playing or video game whose actions are directly controlled by a player of the game 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 it.

Video games typically have one player character for each person playing the game. Some games offer a group of player characters for the player to choose from, allowing the player to control one of them at a time. Where more than one player character is available, the characters may have different abilities, strengths, and weaknesses to make the game play style different.

A player character may sometimes be based on a real person, especially in sports games that use the names and likenesses of real sports people. Historical people and leaders may sometimes appear as characters too, particularly in strategy or empire building games such as in Sid Meier's Civilization series. Curiously, in the case of Civilization, a player's chosen historical character is the same throughout the course of the game despite the fact that a campaign can last several hundred years before and after the lifetime of the real historical persona. Such a player character is more properly an avatar as the player character's name and image typically have little bearing on the game itself. Avatars are also commonly seen in casino game simulations.

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Wikipedia