High-Tech Special Forces Unit FOXHOUND is an elite black ops unit of the United States Army. Established by the "Legendary Soldier" Big Boss.

Although its function has changed over the years, FOXHOUND specializes in covert, solo infiltration, to cope with local revolutions, regional complications, and global terrorist activities in "unauthorized" combat zones too politically-sensitive to intervene through conventional means. Its agents are also trained to complete various missions that are assigned in secret, to the extent that they are considered the modern versions of the ninja. All its members are battlefield hardened veterans, with many coming from a mercenary background. Because of its status as a hi-tech special forces infiltration unit, any and all members of FOXHOUND are heavily trained and rigorously taught a wide field of survival, martial, and operational skills; from a plethora of insertion and maneuvering methods, to skydiving techniques and underwater infiltration, in order to cover all possible routes of infiltration into an enemy nation; advanced outdoor survival skills, including scenarios regarding long period wilderness survival and a wide range of harsh environments; acute stalking, detonation operations, wireless communication, procuring and reusing enemy resources, gathering information, varying martial arts, emergency medical operations, languages, and hi-tech devices.