Protagonist is the main character of a game, which in this case are the Halo Games, in which a player plays as. Such protagonists are Master Chief Petty Officer of the Navy John-117, Lance Corporal "Rookie", Lieutenant SPARTAN-B312 "Noble Six", and Fireteam Crimson.
Halo Trilogy & Reclaimer trilogyEdit
The main protagonist of these games is John-117 aka Master Chief. He is shown wearing MJOLNIR Mark V armor in Halo: Combat Evolved and MJOLNIR Mark VI armor in Halo 2, Halo 3 and Halo 4. Some of his face is revealed at the end of Halo 4, though we do not see all of it.
Halo 3: ODSTEdit
The main protagonist of this game is The Rookie. Like the protagonists in the other Halo games, the identity of his face is not revealed. He also has yet to speak, so his voice is also unknown. He is shown wearing ODST battle armor.
Although the player has the ability to control GSgt. Edward Buck, Corporal Taylor H. "Dutch" Miles, Private First Class Michael "Mickey" Crespo, and Lance Corporal Kojo "Romeo" Agu, the game mainly focuses on The Rookie's journey to reunite with his team.
Halo: ReachEditThe main protagonist of this game is SPARTAN-B312 aka Noble Six. Like the other two protagonists in the other Halo games and Emile-A239, the identity of his/her face has not yet been revealed.
Before the final game, Six's appearance was to look like Thom-293, but Bungie decided to change that idea, and to allow Six's appearance to be the player's Multiplayer Spartan model.