Master Chief
Master Chief Petty Officer John-117 is a fictional person. He is the main protagonist of the Halo video game series. He is also called Master Chief, or Spartan-117.
Master Chief is a player character in Halo: Combat Evolved, Halo 2, Halo 3, Halo 4, Halo 5: Guardians and Halo Infinite. He also is also featured in several novels and other games in the Halo series.
The character is never seen without his green-colored armor and helmet. He is one of the most recognizable characters from Halo. Several action figures of the character are available.