Gray Fox is a character who is both against the terrorist and against Solid Snake. Although he is a major help when it comes to some situations. He will contact snake when he is about to run into something very dangerous, under the guise "deepthroat". His first appearance is when Snake has defeated Ocelot, a ninja in optive camoflauge strikes removing Ocelot's hand, and seeming to save Snake's life. Although he delcares they shall meet soon in the future. The second time he makes a appearance (thats not random) is when he has slaughtered 12 men in the hallway to Hal's research lab. There Snake fights him, as Gray fox spurts out random famous saying such as: Hurt me snake, make me feel it, make me feel alive again.

It is soon then found out, that the Ninja is a old rival from "Outer Heaven" called Gray Fox. He was a leading man in Fox-hound, their bext fighter and only member to receive the code name of "Fox". Although Snake killed him, Naomi explains this Ninja was a process of reviving and experiments to better suit the creations of Genome soldiers. He is killed later by Liquid after saving Snake's life.