FOX logo

The FOX Unit emblem.

Force Operation X (FOX), commonly known as the FOX Unit, was a CIA covert operations group. It was originally led by Major Zero during the Cold War. The unit was specifically designed to handle top secret sneaking and infiltration missions and other black ops. Its most notable agent was Naked Snake, who was only with the unit for a short time during the early 1960s.


FOX was a special services division established by the CIA in the 1960s. Proposed by former SAS operative Major Zero and The Boss in 1962,[1] FOX was a covert missions unit that fulfilled both special operations and intelligence duties. Zero's personal motivations for creating FOX was as a means to prepare himself for an eventual second attempt at recovering a defecting Soviet scientist, Dr. Nikolai Sokolov, of which he was forced to let the Soviets recapture him due to a secret deal made between then-President John F. Kennedy and Soviet Premier Nikita Khrushchev to end the Cuban Missile Crisis. However, it was not until 1964 that FOX became an official branch of the CIA due to the CIA Director frowning upon it previously.[2] Agents were aided in their sneaking missions by unique and advanced equipment developed within their own division, such as the active sonar, motion detector and anti-personnel sensor. FOX mainly operated one-man infiltration missions. Operatives also received extensive training to resist various methods of torture, and truth serum-based interrogation.[3]

FOX was ridiculed as a "group of eccentrics", "weirdos" and "oddballs."[4][5][6]

Operation Snake Eater

See also: Virtuous Mission and Operation Snake Eater

In 1964, FOX's first agent Naked Snake executed both the Virtuous Mission and Operation Snake Eater, succeeding in infiltrating Soviet territory on his own both times. His remote support team included Sigint, Para-Medic and Major Zero. Snake's mission was originally simply to rescue weapons developer Nikolai Stepanovich Sokolov, but it grew to mass proportions, and Snake was eventually forced to destroy the Shagohod, a secret weapon being developed by Colonel Volgin within Groznyj Grad. During the latter mission, Snake commandeered a prototype Sneaking Suit.

Post-Snake Eater

Following the success of Operation Snake Eater, Big Boss (Naked Snake) left FOX and Major Zero retired soon after.

Warning: The following information is from outside Hideo Kojima's core "Metal Gear Saga." It has some level of canonicity within the continuity, but reader discretion is advised.[?]

After 1964, the unit used their first agent Naked Snake's codename as the basis for its Snake-like codenames (i.e. Viper and Boa). Also after 1964, Viper rescued Sokolov from the Soviet Union and, circa 1966, an orphaned girl from East Germany. Due to Big Boss's retrieval of the Soviet Sneaking Suit prototype, during Operation Snake Eater, the FOX Unit reverse-engineered it to create the aromatic polyamide CQC Combat Enhancers, which later became the official uniform of FOX's elite members. At some point, Cunningham (Boa) was sent on a mission, though the outcome forced him to have his right leg amputated and replaced with a prosthetic, and he was later confined to a desk job at Langley. In addition, at some point FOX was put in charge of security for the bunker in the CIA's headquarters at Langley.

San Hieronymo Incident

Main article: San Hieronymo Incident
FOX Unit soldier MPO

FOX Unit soldier, circa 1970.

During the San Hieronymo Incident in 1970, Gene (Viper) became the FOX Unit's squad commander, causing the group to turn renegade on the San Hieronymo Peninsula, and ally themselves with former Red Army soldiers. As a result, Major Zero was arrested by the Pentagon and Naked Snake was charged with treason for supposedly spearheading the revolt. Using the Intercontinental Ballistic Metal Gear, they attempted to attack the Soviet Union, but were stopped by Naked Snake and Roy Campbell, who had recruited some of the disenfranchised Red Army and FOX soldiers to their resistance group. Those in the FOX Unit who refused to take part in the rebellion were killed (excluding Para-Medic and Sigint because they were in the United States and went their own ways).

It was later revealed that the rebellion was actually staged and that FOX were actually obeying the CIA Director, at least at first. The DCI had the FOX Unit steal the Metal Gear, then hand it over to the Soviets and pretend to defect. However, they were also given an alternate order by the DoD (via their agent Cunningham, who secretly allied himself with the DoD out of revenge against his former CIA employers for their treatment of him after he lost his leg) to launch the Metal Gear into the Soviet Union in order to tarnish the CIA's reputation.

Besides the elite members of FOX, regular FOX soldiers were involved in the revolt as well, providing basic grunt duties for high-security areas as well as occasionally acting as backup soldiers in case either the regular soldiers are otherwise unavailable to deter possible intruders or if security measures end up increased. These soldiers were armed with carbines (the XM177E2, the experimental form of the CAR-15 that would later become the M4) and wore camouflage suits similar to Naked Snake's tigerstripe pattern circa Operation Snake Eater in 1964. They also wore black berets with the FOX logo and radio headsets. Some of the regular FOX soldiers also ended up being recruited into Snake's resistance that later became FOXHOUND.

An unintended consequence for the CIA in staging FOX's rebellion was that the bunker under Langley had less security than usual, thus allowing Ocelot to ambush and kill the DCI.

Non-"Metal Gear Saga" information ends here.

Major Zero officially disbanded the FOX Unit in 1970.


Although FOX was disbanded, the official uniform of the Militaires Sans Frontières during the early 1970s included the FOX logo on the right shoulder, in addition to the MSF logo on the left shoulder. Similarly in the late 1970s, a Cipher-affiliated organization XOF used a reversed FOX logo on their official uniforms and on most equipment. One of the Marines also recognized the logo, but couldn't remember from where.[7]

FOX's operations as a covert special forces continued on through its successor FOXHOUND, established by Big Boss immediately after the San Hieronymo Takeover.


Although functioning as a highly able unit backed by advanced technology, FOX excelled in missions emphasizing invisibility both on a physical and political scale. To that end, the concept of OSP (On-Site Procurement) was a standard FOX operating procedure, the idea being that any weapons used in combat were to be those of the enemy's own stock and thus impossible to trace back to the U.S., or FOX, in any way that would prove their involvement. Other details, such as food and other items, were also a part of this methodology; serving to conceal FOX agents and their origin.

This concept of scavenging a mission site would carry on in FOX's successor unit, FOXHOUND. Zero, the founder of FOX, largely based the concept on his own experiences in the SAS, which included bagging any fecal matter belonging to the operative and then bringing it back to their origin when successfully completing the operation. Leaving no evidence behind was the essence of FOX. Anything less than perfect invisibility in an operation was considered sloppy by Zero's standards.

Military resources

Due to its stance as a stealth unit, FOX did not usually utilize weapons outside of OSP (although there have been exceptions, namely if the mission does call to prove America's involvement, such as Operation Snake Eater).

Circa 1964


Warning: The following information is from outside Hideo Kojima's core "Metal Gear Saga." It has some level of canonicity within the continuity, but reader discretion is advised.[?]
Non-"Metal Gear Saga" information ends here.

Codename system

Prior to Operation Snake Eater, various members of FOX had codenames regarding their current occupancy as well as their knowledge in their field (e.g., Sigint being derived from "Signals Intelligence"), or specific references to what their mission plan for FOX is (e.g., the "Naked" in Naked Snake referring to the essentials of OSP in regards to procuring weapons and equipment against the enemy). However, the codenames could also be chosen by the control field, as evidenced by Para-Medic's reasons for giving herself the codename of "Para-Medic", as well as Major Zero adopting the codename of "Major Tom" during the Virtuous Mission as a good luck charm.

Warning: The following information is from outside Hideo Kojima's core "Metal Gear Saga." It has some level of canonicity within the continuity, but reader discretion is advised.[?]

After Operation Snake Eater, members of FOX took their codenames after the family names of various snakes, in honor of FOX's most famous operative, Naked Snake. As such, Python maintained the codename he had used prior to joining FOX.

The name "FOX" also referred to any member of the unit.[8]

Non-"Metal Gear Saga" information ends here.

Former members

Warning: The following information is from outside Hideo Kojima's core "Metal Gear Saga." It has some level of canonicity within the continuity, but reader discretion is advised.[?]
Non-"Metal Gear Saga" information ends here.

Behind the scenes

It is possible that FOX was a unit within the CIA's Special Activities Division (SAD).

The FOX Unit logo was used as the identifier of Solid Snake in Super Smash Bros. Brawl. It is also used as the current logo for Kojima Productions. The Hideochan soldiers from Metal Gear Solid: Portable Ops Plus also wear the FOX logo, or rather, the Kojima Productions logo. The Kojima Productions logo could also be seen on the "armbands" of the soldiers in the Metal Gear Solid 3: Subsistence version of Metal Gear Online, near the elbow.

Fox unit member

FOX soldier in Portable Ops.

Renegade FOX members appear as part of the main enemy force in Metal Gear Solid: Portable Ops, alongside former Soviet army soldiers. They can also be recruited into the player's rebel faction. When in close combat with the player character, they will attempt to knock the player down by slashing them with a survival knife.

Fox soldir

DLC passcode FOX T-shirt and FOX soldier (male and female).

Although FOX is officially disbanded by the time of Metal Gear Solid: Peace Walker, a special UMD for the Entertainment Pack of Peace Walker and the Big Boss Bundle includes in-game, among other things, a FOX camouflage uniform. In addition, around April 6, 2011, Japanese stores also gave out limited copies of the FOX T-shirt. The player, regardless of version, can also get the FOX T-shirt by inputting the passcode included in Play Arts KAI figures of Pupa, Chrysalis, Jungle Fatigues Snake, Sneaking Suit Snake, Cocoon, and ZEKE.

Promotional materials for Metal Gear Solid V: Ground Zeroes revealed another group called XOF whose logo was a near-mirror reversal of the FOX logo. In a later demo for the game, released the same day Kojima Productions' Los Angeles studio opened, it was revealed that one of the necessary steps for the Ground Zeroes chapter was locating a FOX patch that had been discarded earlier among the XOF during their departure.

When completing the nighttime demo for Ground Zeroes at TGS 2013, an animation will play where Big Boss places a FOX logo before it merges with the black background. Something similar would later occur with the E3 2015 demo for Metal Gear Solid V: The Phantom Pain.

Pre-ordering the Bonus Edition of Ground Zeroes will net the player with a bonus Mother Base Staff Member for The Phantom Pain, named FOX, who as the name suggests wears a FOX logo tattoo on the left side of their face.

FOX Unit soldier MPO

FOX Unit soldier A

"A member of CIA Special Forces unit FOX. The brainchild of Major Zero, FOX is a next-generation unit combining combat abilities with spying prowess that has rebelled and taken over the San Hieronymo Peninsula. Supervises the Soviet soldiers."
―FOX Unit soldier A description in Metal Gear Solid: Portable Ops Plus
"A member of CIA Special Forces unit FOX. The brainchild of Major Zero, FOX is a next-generation unit combining combat abilities with spying prowess that has recently rebelled and taken over the San Hieronymo Peninsula. The silent type."
―FOX Unit soldier B description in Metal Gear Solid: Portable Ops Plus
"A member of FOX, a CIA Special Forces unit. The brainchild of Major Zero, FOX is a next-generation unit combining combat abilities with spying prowess. They have rebelled and taken control over the San Hieronymo Peninsula. Something of a gym rat."
―FOX Unit soldier C description in Metal Gear Solid: Portable Ops Plus
"T-shirt with the FOX insignia. Identical in basic characteristics to Jungle Fatigues. Become an honorary member of the legendary Special Forces unit!"
―Fox description in Metal Gear Solid: Peace Walker

The FOX soldiers can be recruited via passcodes in Portable Ops Plus, with the specific passcodes varying depending on whether the game was the Japanese or American version. The passwords are as follows:

Character Japanese U.S.

Notes and references

10978027373 2db12efe4a b

The FOX emblem in Ground Zeroes.

  1. ^ Metal Gear Solid 3: Snake Eater, Konami Computer Entertainment Japan (2004).
    EVA explains in her final session tape that she sent to Naked Snake that Major Zero and The Boss both formed the FOX Unit shortly after she ended up killing The Sorrow.
  2. ^ Metal Gear Solid 3: Snake Eater, Konami Computer Entertainment Japan (2004).
    Major Zero: The CIA director has always frowned upon FOX, but if this mission [the Virtuous Mission] succeeds, FOX will be added to the CIA as an official unit. I intend to make FOX the leader in special operations. And to that end, this mission must succeed.
  3. ^ Metal Gear Solid: Portable Ops, Kojima Productions (2006).
    Gene: It has always been my understanding that a skilled interrogator doesn't have to resort to inflicting pain on his... subject. // Cunningham: You're right, Commander. But it all depends on the time and the place. This man used to be a member of FOX. For him, this doesn't even qualify as torture. I was simply saying hello. [...] It's not part of my normal regimen, but there is a way. // Gene: Drugs? Truth serum won't work on a member of FOX.
  4. ^
  5. ^
  6. ^ Metal Gear Solid V: The Phantom Pain, Kojima Productions (2015).
    Ocelot: [Zero] always did have a thing for oddballs.
  7. ^ Metal Gear Solid V: Ground Zeroes, Kojima Productions (2014)
    Marine 1: All quiet? Hey, did you see those guys' unit patch? // Marine 2: Yeah, a fox, facing right, right? // Marine 1: That's it. You know, it looked just like... // Marine 2: You've seen it before? Where? // Marine 1: I can't remember. I know it had a fox in it too...
  8. ^ Metal Gear Solid: Portable Ops, Kojima Productions (2006).
    Gene: As a fellow FOX, you [Cunningham] know [Snake's] limits.
  9. ^ Though Elisa was bound to her alter persona "Ursula," she never considered herself a part of FOX, specifying her occupation to Naked Snake as "just a medic."