Gray Fox

"Conflict is in our blood. We can't deny it. I was born on the battlefield... And I'll die on the battlefield. All I can do is fight, Snake... all I can do is fight."

- Gray Fox to Solid Snake

Gray Fox, real name Frank Jaeger, was a mercenary and former agent of U.S. Special Forces Unit FOXHOUND. Originally a child soldier, Jaeger was the only operative in FOXHOUND to achieve the codename "Fox," the unit's highest commendation, and was decorated five times.

Fox was Solid Snake's comrade-in-arms and friend during the Outer Heaven Uprising, but his loyalty to renegade commander Big Boss forced him into combat with Snake during the Zanzibar Land Disturbance. Fox survived his injuries following an intense battle, after which he was forcibly outfitted with a powered exoskeleton and subjected to intensive gene therapy. He later confronted Snake as a neutral force during the Shadow Moses Incident, in the guise of the Cyborg Ninja, before dying at the hands of Liquid Snake and Metal Gear REX.

Early life and career
Frank Jaeger spent his early years fighting as a child soldier for FRELIMO guerrilla fighters in the Mozambican War of Independence. Known for his cruel war tactics, he would trick enemies into letting their guard down by acting with "the frankness of a young boy," before killing them with "the ruthlessness of a hunter." This earned him the title "Frank Hunter" from his enemies, which evolved into "Frank Jaeger," as a nod to the little German that he spoke. Throughout the war, Jaeger killed dozens of government soldiers from the Portuguese regime. In 1966, renowned mercenary Big Boss became acquainted with Jaeger in Mozambique after stopping him in battle, and placed the young boy into a rehabilitation facility, believing that he would be safe.

While at the rehab center, Jaeger was taken by the CIA and used as a test subject in the "Perfect Soldier Project." The project turned the boy into a more efficient soldier, capable of killing his targets without remorse, however, it was at a cost. When he was not fighting, he was kept in a fluid-filled sensory deprivation tank which would reset his memories, and suppress his emotions. This intense treatment also enhanced his senses and reflexes allowing him to deflect bullets and become incredibly agile. Because Jaeger was the only surviving test subject of the project, he was deemed a lost number and was given the codename of "Null."

As a teenager, Null, a.k.a. the Perfect Soldier, operated as a member of the FOX unit during the San Hieronymo Incident, under the leadership of Gene. His unique Sneaking Suit color during this time was red. He helped the unit to capture Big Boss, and confronted him in battle during the operation, but was unable to defeat him, their fight ending in a stalemate. However, his fight with Big Boss nonetheless lasted long enough for Cunningham and a squad of FOX agents to arrive and capture Big Boss. Null was forced to let Big Boss live due to Cunningham's insistence that he stand down, though he did so with extreme reluctance.

Despite being laid back into his culture tank, Null's memories of the battle with Big Boss couldn't be erased. He first escaped from the tank shortly after Gene's telephone conversation with Ocelot, killing several FOX agents before finally being subdued by Gene, via throwing knives to the hands and knees, and telekinesis. Driven by a need to kill Big Boss, Null broke free of his chamber a second time and after slaughtering many Soviet soldiers, he confronted Big Boss again at the subpower station. Revealing that his mind was "littered with corpses," and having an almost fatalistic and nihilistic view on life, he asked Big Boss, "Why won't you die? What do you hope to accomplish by living?," before attacking. It was only after this second battle that Big Boss realized who Null really was. Big Boss defeated Null again and convinced him to seek help somewhere outside of the FOX unit.

Afterwards, Jaeger was sent to a hospital, and while he did ultimately survive the events of the San Hieronymo Incident, he was severely wounded both physically and mentally. The doctors and Roy Campbell were also unsure if, after his eventual release from the hospital, he would ever live a normal life after that. Jaeger's battle data as Null was later recovered by Zero, who then revealed this to Ocelot and requested his assistance in a project.

Post-San Hieronymo and FOXHOUND
In 1979, during the Rhodesian Civil War, Jaeger was responsible for killing the parents of a young girl, who would later take the name Naomi Hunter. Feeling immense guilt upon discovering the near-starved child by the Zambezi River, he gave Naomi his rations and chose to adopt her, caring for her as a younger sister. Military analyst Nastasha Romanenko would later speculate that these actions were the result of post-traumatic stress resulting from Fox's childhood experiences in war. His killing of her parents, and his guilt for the action, would continue to haunt Jaeger for the rest of his life, although he kept the true reason for the loss of her parents a secret from Naomi.

At some point, Jaeger returned to Mozambique to participate in the civil war, this time as a soldier for the RENAMO, but would later endure severe torture, during which his nose and ears were cut off. However, he would ultimately be rescued once more by Big Boss.

It was while in Mozambique during the 1980s that Jaeger's "sister" Naomi met Big Boss, who would later take them both to the United States. Jaeger and Big Boss eventually returned to Africa to continue the war, leaving Naomi behind in America.

While living under the alias of "Frank Hunter," during the 1988 Winter Olympic Games in Calgary, Jaeger became romantically involved with Czech figure skating champion Gustava Heffner. The two tried to elope together, but American authorities rejected her bid for asylum and she was sent back to her country, where she was stripped of her competition rights. Following this incident, Jaeger developed a great deal of resentment for his superiors.

Circa the early 1990s, Jaeger served in the U.S. Special Forces Unit FOXHOUND, with Big Boss himself being reinstated as its commander. Jaeger was the only member to receive the unit's highest commendation, being awarded with the codename "Fox." Having been decorated five times, Fox was considered an unofficial leader in FOXHOUND due to his extraordinary soldiering skills and his keen intellect, and was held in high regard among the members of FOXHOUND. During this time, Fox's real name was classified under National Security.

In 1995, Gray Fox was the FOXHOUND agent assigned to Operation Intrude N312. Fox's objective was to gather data on a top-secret nuclear weapon that the fortified state of Outer Heaven was secretly developing. After successfully infiltrating Outer Heaven, Gray Fox scouted the first building of the fortress, noting the locations of the inner courtyard, cameras and elevators, along with various weapons and equipment, such as card keys and Beretta handguns. Sometime afterwards, he stumbled upon information relating to the new weapon being developed. However, the mission ended in failure when Fox was captured, though not before relaying the details of his reconnaissance back to FOXHOUND. His final words before his transmission was cut were simply: "Metal Gear..."

In the follow-up mission, known as Operation Intrude N313, Fox was rescued by rookie FOXHOUND member Solid Snake. Fox provided Snake with all the known facts about Metal Gear; a nuclear-equipped walking battle tank. With Fox's information, Snake located and rescued Metal Gear's creator, and ultimately destroyed the TX-55 prototype that was under development in Outer Heaven. Following Outer Heaven's fall, and the revelation of its leader's identity as Big Boss, all trace of Fox was lost, and it appeared he followed after his commander.

Post-Outer Heaven
After deserting FOXHOUND, Fox accompanied Big Boss to Zanzibar Land in Central Asia. He assisted in the formation of Zanzibar Land through his participation in the Mercenary War and became Big Boss' most trusted lieutenant. After their success in the war, Fox was given his own command among Zanzibar Land's military.

In 1999, the newly-developed Metal Gear D was used to cross Zanzibar Land's borders and conduct raids against several nuclear disposal sites. This act, along with Zanzibar Land's kidnapping of Czech biologist Dr. Kio Marv, led to retaliation from FOXHOUND, then under the command of Colonel Roy Campbell. Solid Snake was pulled from retirement and sent to rescue Dr. Marv, with assistance from the CIA. Fox, conflicted over Big Boss's plans to bring about a new age of global conflict, became a secret informant to his old comrade Snake, justifying it as payback for his selfish desire for battle. During the course of Snake's mission, Fox began transmitting anonymous messages to him, claiming to be his "number one fan," in order to help him overcome certain obstacles and traps.

Fox finally met Snake in person at the Bridge of Sorrow, which he destroyed with Metal Gear, before warning Snake to turn back and leave Zanzibar Land. This action caused the death of his former lover, Gustava, who had been serving the STB and assisting Snake in the search for Dr. Marv. Fox later contacted Snake when the latter's elevator in the Tower Building was immobilized. Because Snake ignored his earlier threat, Fox informed him that the two's friendship was now over. Fox taunted Snake about an impending assault by an assassination squad, the Four Horsemen, but remarking that he would "put up a good fight." Fox's words proved true when the squad failed to eliminate Snake, and though his progress was delayed, Snake reached the detention facility where Dr. Marv was held. Assuming his "fan" alias again, Fox then alerted Snake to Night Fright's presence on the 3rd floor basement, later contacting him again to provide the location of a card key, which Snake required to progress further.

After Snake obtained critical data left behind by a deceased Dr. Marv, Fox activated a pit trap beneath him before he could escape the detention facility. Forcing Snake into an underground facility, Fox, again piloting Metal Gear D, challenged him to a fight, dismissing Dr. Madnar's claims as to its weaknesses. Following Madnar's advice, Snake attacked the bipedal tank's feet with frag grenades where its armor was thinnest, and successfully crippled the machine. Fox survived the resulting explosion and was able to steal the cartridge containing Dr. Marv's OILIX data from Snake. With his opponent having discarded his equipment after having caught on fire, Fox beckoned Snake to fight him unarmed in a room laid with land mines. A fist-to-fist duel then ensued, involving no hatred or murderous intent between the two professionals, with Fox ultimately falling to Snake's repeated blows. Exhausted, and bleeding from wounds to his head, he told Snake that he had supported Big Boss, not because he felt indebted to the man for saving his life in the past, but because he could only find his purpose in battle, despite professing a hatred for war itself. Fox admitted to providing anonymous tips by radio, with Snake assuring the fallen soldier that Gustava would be waiting for him, for which Fox expressed thanks. Snake then left to confront Big Boss, leaving a presumed dead Fox behind.

Rebirth
After the defeat of Big Boss and the downfall of Zanzibar Land, Gray Fox's body, blown apart by a land mine, was secretly recovered by the Patriots. Restored through cybernetic surgery, Fox became a guinea pig for FOXHOUND's chief medic Dr. Clark and her gene therapy experiments. A powered exoskeleton was grafted directly onto his body by inserting a cybernetic module at the skeletal level, granting Fox enhanced strength and agility. Gene therapy was used to help overcome stress concentration and rejection responses.

Subjected to drugs for four years as Dr. Clark and her team continued their research, Fox's responses to gene therapy would ultimately provide research data for the creation of the Genome Soldiers, while nanomachine technology used to suppress his emotions would later be incorporated into the Sons of the Patriots system. Although the experiments Fox was subjected to were classified, rumors nonetheless circulated about cyborg development occurring.

In 2000, Fox's adopted sister Naomi Hunter joined FOXHOUND as Dr. Clark's assistant. She helped Fox to escape his containment in 2003, and summarily covered up his actions when he later killed Dr. Clark, reporting it as a laboratory accident. Fox had actually been used to kill Clark by Big Mama, who had previously recruited Naomi into her organization, as part of a power struggle between opposing factions of the Patriots. Naomi then falsely reported Fox's death during the supposed accident, and helped him hide out. However, the entire ordeal had left Fox's mind unstable, causing a rapid deterioration of identity.

With the desire to face Solid Snake once more in combat persisting within his tattered consciousness, Fox set out to confront him during the Shadow Moses Incident in 2005. Equipped with full-body optic camouflage, the Ninja infiltrated Shadow Moses Island in search of Snake, who was on a mission to neutralize a then-renegade FOXHOUND Unit, led by Liquid Snake. The self-titled Sons of Big Boss became aware of the Ninja's presence on the island after he killed three of their number, resulting in heightened security on the occupied base.

The Ninja first encountered Snake in the base's armory, after releasing ArmsTech President Kenneth Baker from captivity and attacking FOXHOUND member Revolver Ocelot, severing the latter's right hand with his high frequency blade. However, he was forced to retreat after the onset of extremely painful spasms, accompanied by electrical discharges from his body.

This was a side effect of imperfect nerve connections resulting from Dr. Clark's experiments.

The Ninja would later help Snake in his mission by transmitting anonymous messages regarding dangers to Snake, much like he did during Operation Intrude F014, under the alias Deepthroat. This included warning him of hidden Claymore mines north of the tank hangar, and electrified flooring in the nuclear warhead storage building. After taking out a squad of NBC warfare troops ahead of Snake, one of who believed Fox to be a ghost, the Ninja accessed the laboratory of Dr. Hal Emmerich and proceeded to menace the terrified engineer, demanding to know where Snake was. He was confronted by his target shortly thereafter, and told Snake that he was "neither enemy nor friend." The Ninja's bizarre appearance and conduct caused Emmerich to comment that the entire scene was akin to an anime, before hiding in a locker. The Ninja challenged Snake to a battle, feeling that his soul could only find respite in a fight to the death, indifferent as to the outcome. His superhuman reflexes and swordsmanship rendered Snake's gunfire ineffective, only sheathing his sword after Snake engaged him in hand-to-hand combat. At first, Snake did not recognize his opponent, but as the duel progressed Snake began to realize that the Ninja was Gray Fox, and was shocked that he could still be alive. After a time, Snake began to prevail in the battle but before its ultimate conclusion was reached, Fox suffered another painful outburst, and fled the lab. Fox's overall presence, as well as his killing twelve soldiers by the time Snake was captured, caused Liquid and Ocelot to speculate that Fox's presence was due to a spy in their midst.

Gray Fox later joined forces with Snake against Metal Gear REX, and managed to damage the mech by attacking it's radome with his laser gun arm, interfering with the sealed cockpit's sensory input. While its pilot, Liquid Snake, attempted to locate the two, Fox took the momentary break in fighting to reveal to Snake his role in the deaths of Naomi Hunter's parents, and begged him to tell her the truth. Following this exchange, Fox leapt from their hiding spot and again attacked REX. During this second assault, Fox was injured when his left arm was sliced off by the tank's own laser cannon. He was then pinned against a wall by REX's cockpit beak, but was able to destroy the radome while immobilized, declaring that "a cornered fox is more dangerous than a jackal!" in response to Liquid's taunts. Fox was released as REX moved back a short distance, the now-blinded Liquid being forced to open the cockpit, exposing its interior to Snake's Stinger missiles. Fox ordered Snake to fire on the cockpit, but its close proximity to him made Snake reluctant to do so, unwilling to kill his friend in the process. As Snake hesitated, Fox told him that after being taken from Zanzibar Land, he had neither been truly alive nor truly dead, and that he could finally meet his end with Snake to witness it. As Fox fell to the floor, Liquid tried to kill the Ninja once and for all by crushing him under one of Metal Gear's massive feet, but Fox's exoskeleton meant that this first attempt failed. With REX's second stomp, however, the only man considered worthy of the codename "Fox" was no more. His last words were directed towards Snake:

"We're not tools of the government or anyone else. Fighting was the only thing... the only thing I was good at, but... at least I always fought for what I believed in. Snake... farewell..."

Legacy
After escaping the Shadow Moses facility, Snake contacted Naomi, informing her that Fox's last message was to forget about him and move on with her own life, and that he would always love her. Snake decided not to tell her that Fox had killed her parents because he was the only family Naomi had ever known.

During the Big Shell Incident in 2009, Solid Snake referenced Gray Fox's last words to Raiden when explaining why he was motivated to carry out anti-Metal Gear activities. In addition, the Patriots' recreation of Shadow Moses for the S3 Plan had Olga Gurlukovich assume the role of the Cyborg Ninja, causing Raiden to think that Fox may have survived, although Snake and several others knew otherwise.

By 2014, the gene therapy and nanomachine research conducted on Frank Jaeger was utilized in the creation of the SOP system. During this time, Naomi carried a picture of her brother within her locket.

Personality
During his time as the Perfect Soldier Null, his frequent readjustments following each mission deprived him of both his memories and emotions, his only dreams being of waking up to the corpses of his victims lying in front of him, and waiting in vain for his comrades to rescue him. He harbored fatalistic, borderline nihilistic views on life, feeling that it wouldn't truly matter if he spared someone or not as they would die eventually anyway. This belief, as well as his conditioning as the Perfect Soldier, resulted in him developing an intense animosity towards Big Boss after being unable to kill him in battle, and questioning his reasons for living. This aspect eventually resulted in Jaeger renouncing his Null identity altogether when he was defeated by Big Boss.

Gustava Heffner described Jaeger as handsome, well-mannered and intelligent, but always possessed by a level of fear. His cold-blooded nature and extreme tenacity earned him the respect of Solid Snake and others in FOXHOUND, with Snake once considering him better than any other soldier he'd fought with.

Jaeger was fearful around his adopted sister, Naomi, due to the immense guilt that he felt after killing her birth parents. He was reminded of their deaths every time he looked into Naomi eyes.

Fox would become devoted to Big Boss's cause, serving him at the expense of becoming militarily opposed to his friends such as Solid Snake.

Because of his past as a child soldier, Fox's need for the battlefield resonated with Big Boss's vision, despite his own hatred for war itself. Unable to live a peaceful life, it was this helplessness that ultimately led him to side with Big Boss, both feeling that soldiers such as themselves could only find purpose outside of normal society, due to their innate fighting instincts.

After his defeat in Zanzibar Land, Fox developed a yearning for death following his transformation into the Cyborg Ninja, wanting to have one last fight with Solid Snake so he die by the latter's hand. He believed he had been fated to die in Zanzibar Land and so his spirit was broken after his resuscitation by Dr. Clark. After re-encountering Fox the second time, Snake also speculated that the former couldn't remember anything about his past besides their fight in Zanzibar Land. Ultimately, he died aiding Snake in his mission to stop Liquid, achieving the peace he had long sought.

Metal Gear and Metal Gear 2: Solid Snake
Gray Fox (グレイ・フォックス) first appears in the original Metal Gear (spelled "Grey Fox" in the MSX2 version). The player's initial objective is to rescue him and obtain intel on Metal Gear from him. Fox's sprite in the MSX2 version was a recolor of the regular prisoner of war sprite (wearing a blue jumpsuit instead of a brown one), or in the case of the Nintendo Entertainment System version, the same as the prisoner of war sprite (as the game's characters were monochrome). In addition, Fox's role is very minor, as he only gives Snake the details of the TX-55 Metal Gear and suggests that he find Dr. Madnar before disappearing altogether. Future installments added some more detail to the meeting, revealing that Fox also showed a green Snake "the ropes."

In the Previous Operations section of Metal Gear Solid, Fox's mission is erroneously referred to as "Operation Intrude N313" instead of "Operation Intrude N312."

Fox returns in Metal Gear 2, where he confronts Snake as an enemy on several occasions, while secretly assisting him as an anonymous informant. Fox's past is fleshed out in this game and his civilian identity is revealed to be Frank Jaeger (フランク・イエーガー) ("Frank Yeager" in the MSX2 version).

Fox is the most recurring boss character in the series, being fought in a total of five boss fights throughout the games (Vamp, Liquid Snake and Revolver Ocelot are fought four times, respectively throughout the series).

Fox's portrait was modeled after actor Tom Berenger. In the re-released versions, he was redesigned to resemble his later depiction in Metal Gear Solid. Portions of Fox's character, namely his first name of Frank, as well as his attempting to elope with a Czech figure skater, were influenced by the novel Crossfire.

It is stated in Metal Gear 2, and again in Metal Gear Solid, that the hand-to-hand battle between Snake and Fox takes place on a minefield. However, Fox is able to move around freely during the fight and can only be defeated by the player. Also, while Fox does "explode" after his defeat and "final conversation" with Snake, this is the case for nearly all the bosses in the game, except Dr. Madnar.

Early backstory
In Metal Gear 2, Fox claims that he was a half-white living in Vietnam, sent to a forced labor camp after the war, which ended on April 30, 1975, before Big Boss saved him for the first time. In addition, the Metal Gear Solid: Official Mission Handbook states that he was born in the 1970s to unknown parents, and was of Vietnamese and German-American descent. However, Metal Gear Solid: Portable Ops later contradicts the Handbook 's account with his appearance in 1970, though he retains a German-speaking background. Finally, Metal Gear Solid V: Ground Zeroes reveals that Big Boss was in a coma before the Vietnam War ended and did not wake up until 1984, contradicting Fox's account in Metal Gear 2.

While some of the events detailed in Metal Gear 2 remain plausible, despite both Fox's recollection, and the more recent story developments in Portable Ops, they are omitted from the Metal Gear Solid 4 Database. Fox's later activities during the Mozambican Civil War are referenced in Metal Gear Solid. In Metal Gear 2, Fox states Big Boss saved him while he was a child soldier for the RENAMO, the anti-Communist guerrilla that fought FRELIMO during the Mozambican Civil War. In Metal Gear 2, Fox states Big Boss saved him while he was a child soldier for the RENAMO, the anti-Communist guerrilla that fought FRELIMO during the Mozambican Civil War. However, it is implied in Portable Ops that he partook in the Mozambican War of Independence on the side of the Marxist-Leninist FRELIMO.

Metal Gear Solid and Portable Ops
In the English versions, Gray Fox was voiced by Greg Eagles (credited as George Byrd) in Metal Gear Solid, Rob Paulsen in The Twin Snakes, Super Smash Bros. Brawl, and Metal Gear Solid 4 and Larc Spies in Portable Ops. In Japanese versions, he was voiced by Kaneto Shiozawa in Metal Gear Solid and Metal Gear Solid 4, Takumi Yamazaki (the same man who voiced Ocelot in Metal Gear Solid 3) in Metal Gear Solid: Bande Dessinée and Jun Fukuyama in Metal Gear Solid: Portable Ops. In the Japanese versions of Super Smash Bros. Brawl and Metal Gear Solid 4, Fox utilized the vocal archives of Shiozawa due to his death in 2000.

Fox's Cyborg Ninja design was created by series artist Yoji Shinkawa. The design did not exist in the original concept for Metal Gear Solid, but director Hideo Kojima liked it so much, he decided to incorporate it into the storyline, based on a sketch by "Shin-chan" that he found. When Fox's face is unmasked in the latter stages of the game, the pupil of one of his eyes is shown to be white.

The codename "Deepthroat," which Fox used when contacting Snake by Codec to offer him advice, was also the name of the FBI agent who exposed U.S. President Richard Nixon's involvement in the Watergate scandal. FBI agent William Mark Felt was the real Deepthroat, and he revealed himself to the public in May 2005.

In IDW's Metal Gear Solid: Official Comic Book, it is hinted that Fox was sent by the Patriots to find and kill Solid Snake, in order to facilitate the job of assassinating him themselves.

The Ninja's role in The Twin Snakes remake was similar to the original game, but was slightly extended due to directorial decisions. Specifically, a new action-packed cutscene shows his slaughter of the Genome Soldiers guarding Dr. Emmerich's lab, with Snake briefly witnessing this (in the original game, the attack is heard off-screen, with Snake deducing the Ninja's involvement upon discovering the body-strewn hallway).

Portable Ops, a prequel set two decades before the events of the first Metal Gear, features a teenage Fox as a masked machete-wielding soldier named Null (ヌル). The revelation of his identity in Portable Ops is similar to that in Metal Gear Solid; in both cases, his identity is unknown until he is engaged in battle and defeated by the player.

"A child soldier and member of the CIA Special Forces unit FOX, Null is also known as the Perfect Soldier. Possessing superhuman physical abilities, this invincible warrior has defeated every opponent he has faced."

- Character description in Metal Gear Solid: Portable Ops Plus

In the novelization of Metal Gear Solid, Fox's death was portrayed in a slightly different manner than in both the original game and the remake. Namely, Fox managed to destroy Metal Gear REX's radome at exactly the same time that the mech stepped on him, thus failing to crush him to death in that instant. However, he was still gravely wounded from the attack, and as a result, he died shortly afterwards. The remake, The Twin Snakes, was also slightly different in doing Fox's death, as it only utilized one stomp attack to kill him, with it gradually delivering an increasing amount of pressure on Fox until his exoskeleton caved. REX then wiped its foot on the floor.

In the novelization, the gun that Fox used against REX was specified to be a portable Vulcan cannon, while in Shinkawa's character design sheets and product details for the Cyborg Ninja Play Arts Kai action figure, it is simply referred to as a "Laser Gun Arm."

Other references in the Metal Gear series
Although Gray Fox himself does not appear in Metal Gear Solid 2: Sons of Liberty, due to it taking place after his death, he is mentioned a few times in the game. Likewise, in Substance, Raiden can wear a Cyborg Ninja outfit bearing multiple similarities to Gray Fox's exoskeleton in the VR missions.

Gray Fox is referenced several times in Metal Gear Solid 4: Guns of the Patriots.

Super Smash Bros. Brawl
In Super Smash Bros. Brawl, Gray Fox appears as an Assist Trophy who leaps around the arena and attacks opponents with rapid sword-slashes. He also deflects any projectiles fired at him. He also has the ability to reappear from the top of the screen if he falls off the stage. If one of the players is in control of Solid Snake and the Gray Fox assist trophy is activated, the two characters will exchange in dialogue from Metal Gear Solid. An unlockable trophy of Gray Fox exists within the game, with the following text:

"An enigmatic soldier with great physical and combat skills. Calling himself 'Deepthroat' and equipped with an enhanced environmental camouflage suit, he dedicated his life to fighting Snake. In a twist of fate, Gray Fox ends up protecting his sworn rival from Metal Gear REX. Long ago, Gray Fox fought Snake in Zanzibar Island."

Besides his appearance as both a regular and an assist trophy, Gray Fox also appeared as a sticker in the same game. Characters who wore the sticker will increase flinch resistance by 98.

He was also indirectly mentioned twice, both by Solid Snake during Codec calls: When calling Roy Campbell about Fox McCloud, Snake will comment that he's "getting sick of Foxes", alluding to both FOXHOUND's going renegade as well as Gray Fox becoming his enemy in Metal Gear 2. Snake also mentions he empathizes with Marth about getting betrayed by close ones in a Codec conversation with Mei Ling on Marth, alluding to Gray Fox betraying Snake in the same game alongside other characters in other games and betrayal being a repeated theme of the franchise.

References in other media
ScrewAttack ranked Gray Fox #2 in their Top Ten Ninjas list.

Play Arts Kai has released action figures of Gray Fox in his Cyborg Ninja form, which had three models: One was the regular variant used in the game, one was based on the bonus-colored variant, and the last one was primarily gray. The bonus-colored variant was recently released at the San Diego Comic Con as an exclusive item, alongside four Metal Gear Solid-themed iPhone cases and a 25th Anniversary T-shirt.

He also appeared in Vs. Battle, where he challenged Raiden. Earlier, his skin from Metal Gear Rising had challenged Solidus Snake. In addition, his "Fight to the Death" dialogue with Snake also competed with Sniper Wolf's Love Letter dialogue in the same contest.

"STRENGTHS: The Cyborg Ninja that Set the Bar WEAKNESSES: The Cyborg Game has Moved On FEATURED FACT: Gray Fox developed a tormented desire for death at Solid Snake’s hand after Zanzibar, but actually found eternal peace aiding him against Liquid FEATURED GAME: METAL GEAR SOLID: THE LEGACY COLLECTION"

- Gray Fox's bio in Vs. Battle; Raiden v. Gray Fox

"STRENGTHS: Getting to Play Gray Fox in RISING WEAKNESSES: Did You Just Read the Above? FEATURED FACT: Gray Fox & Raiden share much, such as lethal skills & lifelong torment born from child soldiery FEATURED GAME: METAL GEAR RISING: REVENGEANCE"

- Gray Fox MGR Skin from Versus Battle

"STRENGTHS: Epic Duel WEAKNESSES: Someone Had to Win FEATURED FACT: Like Sniper Wolf, Gray Fox is one of the most popular METAL GEAR SOLID characters ever and gave Solid Snake everything he could handle FEATURED GAME: METAL GEAR SOLID: THE LEGACY COLLECTION"

- "Fight to the Death" from Versus Battle

Metal Gear Rising: Revengeance
"A chassis patterned after Gray Fox's body circa the Shadow Moses incident, but functionally equivalent to recent cyborg bodies. Though it was termed an "exoskeleton" in those days before the advent of modern cyborg technology, it could not be taken on and off at will."

- Gray Fox description in Metal Gear Rising: Revengeance

"The high-frequency Blade used by ex-FOXHOUND field agent Frank Jaegar, a.k.a. Gray Fox, after he was outfitted in a cyborg ninja chassis by Dr. Clark. Gray Fox's soul still echoes through the blade, sometimes enabling it to cut clean through enemies, armor and all."

- FOX Blade description in Metal Gear Rising: Revengeance

Gray Fox is a downloadable costume for Raiden in Metal Gear Rising: Revengeance. The first HD screenshot of the costume was published on January 10, 2013 at 2:50 pm by the Metal Gear Rising Facebook page as a reward for getting 200,000 likes to Metal Gear Rising. The overall design for the Gray Fox skin is based on the Play Arts Kai figure for Gray Fox's normal appearance. A pre-order also came with the Gray Fox skin, as well as a special weapon called the Fox Blade, based on the weapon Gray Fox used in Shadow Moses. The English Gray Fox trailer also revealed that the Fox Blade was upgradable, and that its limits were "epic." With it, the player is only required to cut once while in blade mode to get cyborg organs to recharge. In the Japanese DLC skin trailer, when showcasing the Gray Fox skin trailer, it showed Raiden's Gray Fox skin slaughtering several cyborg ninja soldiers, a reference to a scene in Metal Gear Solid where he first appeared as a Cyborg Ninja. The descriptions for both equipment indicate that the Gray Fox skin was actually a copy of the exoskeleton Gray Fox wore in Shadow Moses, and that the FOX Blade was not only the same weapon, it was also infused with Gray Fox's soul. Despite the latter description, it does not share any of Gray Fox's voice actors, unlike the Snake's Soul Wooden Blade.

Besides the DLC, Gray Fox was indirectly alluded to in an optional Codec conversation with Maverick member Courtney Collins, regarding the advancements in cyborg technology, establishing the cause of his painful spasms in Metal Gear Solid as being from faulty nerve connections to his exoskeleton.

On January 17, 2013, Kojima told IGN that it was the development staff's decision to use Raiden as the main character of Metal Gear Rising. He admitted that if it were up to him, he would have used Gray Fox instead. He also admitted that had Fox been used, he would have ended up writing and directing the game.

Ground Zeroes
A Gray Fox skin is unlockable in Ground Zeroes, using graphics from the PlayStation version of Metal Gear Solid, although it is noticeable that he has Solid Snake's polygonal face and bandana. The specific methods of unlocking the skin involves not only beating the Déjà Vu mission on Hard, but also answering the questionaire with 100% accuracy on the same difficulty. Miller when conducting the quiz during either first time playthroughs of the hard difficulty or otherwise redoing the quiz due to failing earlier will also allude to this skin by stating that he has a special bonus thrown in if the player answers all questions correctly, as well as stating upon doing so that he'll give the bonus later. If the player does a dash, he will move at a superhuman speed and have lightning emit from his legs, similar to Raiden in Jamais Vu, and was also potent enough to kill Ravens and mice via contact.

Aside from the game itself, Gray Fox (identified as Cyborg Ninja) is also an unlockable officer character in the Mother Base Developer on the Metal Gear Solid V: Ground Zeroes Companion App. He is unlockable by achieving 85k points in Deja Vu's hard mode.

The Phantom Pain
A leaked scan for an Italian game guide for Metal Gear Solid V: The Phantom Pain revealed that Gray Fox will act as a skin for Venom Snake, alongside Raiden. The scan also revealed that running into enemies will knock them down, stunning them long enough for the player to CQC them by the time they get up. The skin could be unlocked for development by getting the Master Certificate (Standard), which is accomplished by completing all regular missions.

During the development of The Phantom Pain, a theory circulated online that the Venom Snake featured in the game was actually Fox, citing that in gameplay and cutscene trailers, several of the camera angles resembled Fox's scenes in Metal Gear Solid. While the theory became popular with some fans, it was later disproven.

Metal Gear Solid
In Metal Gear Solid and The Twin Snakes, if the player neither manages, nor attempts, to escape the torture room's holding cell after Ocelot's five torture sessions, Gray Fox will appear and open the door for Snake before disappearing. If player doesn't get rid of the timer bomb, he calls Snake when timer has 60 seconds left. Also, upon completing the game twice, Gray Fox's Cyborg Ninja outfit will be changed from blue and brown to red and blue, resembling Spider-Man and Deadpool from Marvel Comics.

If the player uses chaff grenades to attack Gray Fox during the fist fight, he will be stunned, but then tells off Solid Snake for his cheap method of attacking, citing that this was not how Snake usually fights, and resorts to attacking Snake with his sword as a result.

Metal Gear Solid: Portable Ops
When fighting Null at the power substation, several of his quotes sound a lot more agitated compared to when he said them during the fight at the silo entrance. To unlock Null, simply defeat him both times and begin a second playthrough after beating the game.

In battle, Null uses a Machete for fighting at close quarters and deflecting bullets and uses M10 otherwise. Upon recruitment Null comes with a Machete as a unique weapon with an attack pattern similar to that of the unequipped punch punch kick attack pattern, and the third swipe is always lethal towards non-boss or regular opponents.

Null uses his machete in the left hand while battling him or while playing as him, but in cutscences Null use his machete in the right hand.

During both his boss fights, he says his taunts in a slightly differing tone for each battle. In the Silo Entrance, he says them in a robotic monotone. In the Power Substation, however, he has a noticeable increase of agitation in his tone.

Metal Gear Solid 4: Guns of the Patriots
During Act 4, when the player arrives at the Supply Port where REX's remains are, taking a picture of REX's left leg will unveil a ghost of Gray Fox while he was a Cyborg Ninja. His calling Snake to warn him about the claymore mines and tank in the canyon area was also an unlockable audio flashback.

In addition, one of his lines during the fight in Metal Gear Solid, "Hurt me more!", was also the name of a trophy in the game's trophy patch, unlocked when the player uses the Metal Gear Mk. II/Mk. III to electrocute an enemy soldier.

Appearances

 * Metal Gear
 * Metal Gear 2: Solid Snake
 * Metal Gear Solid/Metal Gear Solid: The Twin Snakes
 * Metal Gear Solid: VR Missions (non-canon)
 * Metal Gear: Ghost Babel (mentioned; non-canon)
 * Metal Gear Solid 2: Sons of Liberty (mentioned and flashbacks)
 * Metal Gear Solid: Portable Ops
 * Metal Gear Solid: Portable Ops Plus (non-canon)
 * Metal Gear Solid 4: Guns of the Patriots (mentioned, flashbacks, voice, ghost, picture and paintings; ghost and paintings are non-canon)
 * Metal Gear Solid: Social Ops (trading card)
 * Metal Gear Rising: Revengeance  (indirectly mentioned and alternate costume for Raiden; costume is non-canon)
 * Metal Gear Solid V: Ground Zeroes (alternate costume for Big Boss; non-canon)
 * Metal Gear Solid V: The Phantom Pain (alternate costume for Venom Snake; non-canon)