A player character is the protagonist of the game. Remarkably silent, the player character is the avatar of the player; it is left up to the latter to "fill in" what they imagine the character is feeling, thinking and acting, thus immersing the player within the world of the game.
The player character is a Pokémon trainer beginning their Pokémon journey. They start their journey in their hometown by getting a starter Pokémon, a Pokémon that appears very early in their native region's Pokédex, and is of the Grass-, Fire- or Water-type. The region's native Pokémon Professor will give them this, as well as a Pokédex.
Players can choose which of two available characters to play as. They have a rival who begins their journey at the same time.
Players take part in several events, and meet a great number of Pokémon and people during their adventure. A common target is to conquer the Pokémon League's eight Gym Leaders and Elite Four, and become the Champion. Several additional sidequests occur during and after the game's main plot.
In Pokémon Sage, the male player character is Simon, and the female player character is Sofia. They are childhood friends and neighbors from Dacapo Town. The character who the player does not choose to play as will act as a friendly rival.