There’s an air of mystery surrounding Halo’s protagonist, the Master Chief, likely owing to the fact that we never see his face in the games. Combined with his extraordinary strength, speed, resilience, and other qualities far exceeding those of average humans, it’s easy to wonder whether the character is even human at all. Occasionally, enemies in Halo Infinite will call out to Chief in combat, referring to him as a “robot,” but is he actually a robot?
The answer is a definitive “no,” Master Chief is not a robot; he is a human, albeit a genetically-enhanced one. In Halo 4’s Legendary ending, we get to see part of his face, which establishes he has human-like features. Halo lore establishes that Master Chief was born to human parents on the planet of Eridanus II. Known solely as “John” back then, he was entered into the Spartan-II program at the age of six, and by the time he was 14, he underwent an augmentation procedure that granted him super-human strength, size, and speed. Additionally, Master Chief’s face has actually been shown several times in Halo media outside of the games, further demonstrating that he is, indeed, a human.
Enemies in Halo Infinite likely refer to Master Chief as a robot due to the robotic appearance of his armor. It’s probably an assumption founded on the fact that the character has no visible skin or facial features. Of course, it’s always possible they could be teasing him as well. That said, the Halo lore has established beyond a shadow of a doubt that the character is a human.