Player

From Styleguide

player

A person playing a game.

Use specific names or terms like avatar or player character to refer to the character the player is controlling.

In multiplayer games, characters can be referred to generically as player one, player two, and so forth (don't use numerals).

In massively-multiplayer games, different players should be referred to by the names of their characters.

Example: In the Teenage Mutant Ninja Turtles arcade game, player four controls Donatello.

Also see: avatar, character, multiplayer, player character.