For more general uses of the term Syphon Filter, see this page.


Thomas Markinson, Syphon Filter


Syphon Filter virons seen through a microscope.

Syphon Filter is a virus, the title of the Syphon Filter Franchise and the name of the first game in this series.

It is essentially a biological WMD - Weapon of Mass Destruction - sought after by terrorists and The Agency, all of whom seek to use it for their own nefarious, dastardly endgames. It is particularly notable for being able to target specific genotypes, leaving certain people alive while killing only its victims.



Vincent Hadden and Lawrence Mujari, Syphon Filter 3

Testimonial information from Lawrence Mujari indicates the virus was originally discovered sometime in August of 1984, deep within Pugari Gold Mine, Mpumalanga, South Africa, when the African National Congress sent Mujari with two fellow soldiers to explore the region. Viral samples were collected sometime after discovery. The Agency, having received word of the virus' capabilities as a bio-weapon, sent Agent Teresa Lipan to collect viral samples from Mujari. These samples were then analyzed by Pharcom, an agency subsidiary.[1]


SFV has been shown to attack the cells of plants endogenous to South America and Africa through an unknown mechanism.[2]


The virus started, of course, as a potent bioweapon, but as you can see we we've progressed far beyond that. Think of it as a supercomputer, a nanomachine that can be programmed on a genetic level. This is just the beginning! The Syphon Filter virus is the next millennium. With the virus and its delivery system, no cell is immune. Cancer cells will become a thing of the past!

Elsa Weissenger, Syphon Filter 2

Syphon Filter is a icosahedral retrovirus that possesses ribonucleic acid reverse transcriptase which allows it to integrate into the host's deoxyribonucleic acid. Due to the high error rate for transcription, the virus has been known to evade white blood cells. Furthermore, it can essentially masquerade as the victim's immune system using CCR4 adhesion and integration, consequently resulting in exponential reproduction. The loss of immune cells increases the risk of opportunistic infections.

SFV has also been seen to possess exceptionally high viral tropism, invading almost every cell in the human body via the lysogenic cycle. When virons affect blood cells, atrophy and apoptosis follows, leading to an array of symptoms, including but not limited to: low blood pressure, tachycardia, syncope, pallor, and hypovolemia. Loss of oxygenation from red blood cells initially results in hypoxemia and, eventually, necrosis of infected tissues. Necrosis of blood vessels leads to subsequent haemorrhaging.

When expressed in nervous tissues, SFV also releases lysogenic prions[3] after being destroyed in glial cells. These prions form a misfolded template for lysine receptors expressed in neural tissues. Such a process potentates possible neurological effects.

Dr. Jandran, a former SFV researcher, noted that the actions of SFV are strikingly similar to Bovine Spongiform Encephalopathy (also known as Mad Cow Disease) and Human Immunodeficiency Virus.[4]

Syphon Filter also exhibits a degree of potential to battle diseases such as cancer because it can liquidate almost any cell.[5]

The virus employs multiple transmission methods - primarily, direct fluidic. To avoid being infected with such pathogens, one must take extreme care to avoid contact with viscous fluids and aquifiers at all costs. It can be transmitted via waterborne mediums, including in liquid forms and any bodily fluids.[6]

Antidotes and remedies

"There is no universal vaccine. You have to know the specific genetic lock and key for each programmed virus. Only Phagan's computers have that information!"

Lian Xing, Syphon Filter

Unusually for a virus, and owing to the fact that it binds with the victim's individual genetic information, Syphon Filter does not possess a universal vaccine. It is only the administration of a specially concocted combination of viral RNA, DNA ligase and lysogenic inhibitor proteins specific to a particular victim that can effectively destroy the pathogen.[7]

The virus can cause those infected to black out, which can be temporarily staved off with injections of adrenaline.[8]


Soon she'll look like a walking corpse...It's going to be a slow painful death!

Lyle Stevens, Syphon Filter 2

The symptoms of Syphon Filter include, but are not limited to:

Notable victims

  • Jonathan Phagan (infected, brain-dead due to Mara Aramov's bullet inside his head and later succumbs to his injuries; Dillon Morgan turns off his life support. He was never cured)
  • Lian Xing (infected and cured of the virus)
  • Rhoemer's test subjects (infected, some die from the virus, others are killed by a 'vaccine' that was issued by Markinson to Gabe, at least one survives)
  • Nikolai Jandran (infected, dies from a serum issued by Dr. E to Agency operatives)
  • Jandran's assistant (killed from reckless exposure)

Notable researchers


Syphon Filter

Syphon Filter was presumably first grown on Rhoemer's Costa Rican Plantation. When he was informed by Benton that Gabe Logan and Lian Xing were sent to investigate his activities, he had Girdeaux incinerate the entire area and Mara Aramov to execute Ellis. Nonetheless, a few patches of plants were left undamaged, and Gabe was able to recover these for further research.

Upon returning to Washington, DC, Gabe and Lian find out about an outbreak in Nepal, in which Rhoemer had unleashed the virus. Most of the people were killed, but there was a lone survivor, something Lian described as 'impossible'.

Before Gabe and Lian could pursue Rhoemer, the terrorist declared war on the USA and assaulted Washington, DC. He placed several bombs filled with Syphon Filter in the park and the main one in Freedom Memorial. When he was in the subway system, Gabe encountered a decoy that was programmed as an explosive. He barely escaped from the device intact; the resulting devastation levelled the Washington Subway.

After apprehending Mara Aramov for the first time, Gabe arrived at the Washington Park and rendered assistance to CBDC personnel in diffusing the scattered explosives. He terminated Jorge Marcos and eventually arrived at Freedom Memorial. Forced to avoid using explosives in his fight with Girdeaux (to stop the main bomb from detonating), he ultimately found a weakness on the Frenchman's armour. Girdeaux screamed in agony as he was immolated from the inside out.

After failing to infect Washington, DC, Rhoemer retreats from the area. Gabe's investigation takes him to a new lead from PharCom, a multinational pharmaceutical and biotechnology corporation headed by Jonathan Phagan. The Costa Rican plantation was growing PharCom compounds, meaning Phagan and Rhoemer were in cahoots. At the PharCom Exposition Center, Gabe shadows Phagan to a meeting with Aramov and Edward Benton, an apparent Agency mole who assisted Rhoemer during the Washington, D.C. attack.


Markinson gives Gabe a report on Syphon Filter, a bioweapon that one can program on a genetic level to target specific groups of people. Gabe and Markinson infiltrate Rhoemer's stronghold in Ukraine to inject infected test subjects with what Markinson makes him believe is a vaccine; he also locates Phagan, who is now Rhoemer's prisoner. In the catacombs, Phagan tells Gabe that Lian is alive, and they reunite. Lian has become infected with Syphon Filter, and she says there is no universal cure.

Mara Aramov arrives to shoot Phagan, but she convinces Gabe and Lian that she came to help. The group travel to PharCom's warehouses in hopes of preventing Rhoemer from launching a missile. Lian reveals that the serum Gabe injected into the test subjects was in fact a lethal chemical, and Markinson was negotiating their deaths. Using the infighting between Rhoemer's terrorists and Phagan's security personnel to cover his insertion, Gabe descends into a silo and searches for the missile's detonation codes.

He finds Markinson and gets him to confess that the Agency has been involved in the plot all along. Rhoemer in fact worked for Markinson, since the latter wanted the virus in the Agency's possession. He never authorized the missile attack, but before he can stop it, Rhoemer kills Markinson with a pistol. Gabe must reach the missile's control center in time and destroy it. Infuriated, Rhoemer engages Gabe in a final fight, but is killed with a gas grenade.


Syphon Filter 2

Syphon Filter 2 focuses on curing the now-infected Lian Xing. Gabe and Lian are currently targets of the Agency and enemies of the state after uncovering the organisation's connection to Syphon Filter. Agency operative Dillon Morgan captures Lian at the PharCom warehouses, forcing Gabe and the CBDC to rendezvous with ex-agent Teresa Lipan in Arizona. Simultaneously, Agency-scrambled F-22 Raptors down their transport over the Colorado Rockies, so Gabe and CBDC Lieutenant Jason Chance head down the mountain in search of their plane and a box of PharCom data disks. Michael Archer of the Agency attempts to stop them at all costs. 

A group of conspirators, including Mara Aramov and Agency director Lyle Stevens, agree to deliver the virus to a rogue Chinese general named Shi-Hao. Meanwhile, Lian recovers in a U.S. air force base where Morgan and two operatives are working with Dr. Elsa Weissinger of PharCom to extract infected plasma from test subjects. Lian learns that the other subject was Phagan, who survived his gunshot wound long enough for the Agency to take the plasma. Weissinger attempts to keep Phagan alive for research, but Morgan, intending that the government not find Pharcom's CEO infected with an unknown virus, deactivates his life support to tie up a loose end.

Lian eventually escapes the medical building and interrogates Agent Thomas Holman to learn that Morgan is planning another operation to the PharCom Expo Center to find an encryption disk. She leaves the base in a helicopter and teams up with Gabe to battle Archer's forces. Gabe shoots Archer during his escape, and recovers the PharCom data. 

The protagonists follow Holman's lead to the Expo Center and kill Morgan before he can recover the disk he sought. After decrypting the PharCom data, Teresa realises that some information is missing. The other half must be with Uri Gregorov, director of the Russian SVR, who appeared at the warehouses before Gabe left. Since Lian and Uri know each other, they arrange to meet in Moscow. 

Aramov instigates a gunfight while they meet and Lian pursues Gregorov. Lian later learns he is an impostor working for Mara and trying to find the other half of the data. The man confesses that the real Gregorov is in a Russian gulag, Aljir Prison, which once held Lian. Gregorov uncovered a plot to sell the virus to Shi-Hao, so Aramov intervened. Lian goes to stop Gregorov's execution, but collapses from the virus. Gabe takes her back to the States, while Gregorov promises to handle Shi-Hao. 

Gabe and Teresa arrive back at the Virginia safehouse overseen by Lawrence Mujari, a freelance pathologist. They decide to trade the PharCom data to the Agency for Lian's vaccine. Director Stevens double-crosses Gabe in the Agency's New York City labs, but Logan escapes and forces Dr. Weissinger to give him the vaccine. Gabe also finds out that Chance survived the mission in Colorado, and sets him free. 

Pursued by a joint team of NYPD SWAT cops and Agency personnel, Gabe and Teresa hurry back to their helicopter. When Stevens attempts to shoot Gabe, Teresa destroys part of the streets to knock them into the sewers. Gabe and Teresa eventually turn the tables, shooting Steven in cold blood. Assuming that Chance was killed since he failed to respond to radio calls, Gabe brings Teresa to the rooftop.  

They reach the helicopter to find Chance waiting in impenetrable Agency-issued super-armor. He was really working for them, and he seemingly kills Teresa. Gabe suspected it since the Agency always knew where he was in Colorado. Both men fight, and Gabe kills the man he trusted with an assault shotgun that drives Chance into the helicopter blades, decapitating him.

A news report reveals that the Agency's existence is now public, and U.S. Secretary of State Vincent Hadden promises that the government will investigate. Gabe cures Lian and demarcates a grave for Teresa. He, Lian, and Lawrence hold a small memorial and promise to keep fighting, while soldiers watch them from a distance. In a post-credits scene, Hadden and Aramov emerge from a helicopter, with Aramov saying that the Administration will soon fall allowing Hadden to become President. Although he could end it here, Hadden has other plans for Gabe.

Syphon Filter 3

Unlike the previous game, which was a sequel to the original instalment, Syphon Filter 3 contains numerous flashbacks to show how each character was introduced to the virus. Secretary of State Vince Hadden brings in Gabe, Lian, and Mujari to testify in Congress about their relationship to the Agency. He considers all three to be guilty, and questions them after they assassinate Shi-Hao from a hotel in Japan to stop the general from acquiring Syphon Filter. The three do not realize that Hadden is involved in the conspiracy, and is looking for scapegoats.  

Gabe begins by describing the first Syphon Filter investigation. He and Lian went to Costa Rica to find missing Agent Ellis. When they arrive, the two see that Erich Rhoemer has ordered Ellis killed, but Gabe must continue his mission and identify what Rhoemer was doing at the drug plantation. Gabe chases Rhoemer onto an airplane despite his Agency superior Edward Benton warning against it. Gabe did not know back then that Benton and the Agency controlled Rhoemer, who escaped from the plane.  

Mujari testifies next, and tells Hadden how he once worked for a resistance during the Apartheid era in South Africa. At the Pugari Gold Mine, he discovered that mining slaves had caught a deadly plague and the mine owners were covering it up. Mujari retrieved samples and gave them to Teresa.  

When it's Lian's turn to testify, she mentions her first meeting with Gabe during the Soviet occupation of Afghanistan. Lian was working for the Chinese MSS, and Gabe saved her from an ambush. In turn, she agreed to distract Soviet forces so he could move a convoy of weapons into Kabul.  

During Lian's testimony, Gabe goes to Ireland with Mi6 agent Maggie Powers in an effort to sink a shipment of Syphon Filter. Onboard the S.S. Lorelei, Gabe plants several explosives and finds a document that will point to a virus test site in Australia. He also looks for any information on the mysterious arms consortium that controls the Agency. With the bombs set, he and Maggie leave the freighter.  

While Lian is describing how she met Elsa Weissinger at the Costa Rica mission, Gabe and Maggie fight IRA terrorists looking to take the virus themselves. Gabe uncovers a mole in Mi6, Nigel Cummings, who is aiding them. He kills Nigel and secures the last viral transport on the docks. Then they sink the S.S. Lorelei.  

Back in Washington, D.C., Gabe talks about his first meeting with Benton in Afghanistan. Benton claimed to be a CIA agent transporting weapons to Afghans rebelling against the Soviets, but when Gabe and Ellis escort the convoy, the Afghans attack them. Gabe gets into Kabul and meets Lian, who sets up the diversion. However, a tank gets in their way, so Gabe destroys it. He learns that Benton was supplying arms to the Soviets, and was really an Agency operative.  

As Hadden questions Gabe, Lian teams up with Maggie to kidnap Elsa from the Australian test site. Elsa is ready to betray the conspirators since Aramov left her behind, and she has Lian assemble a vaccine for aborigines held captive by Commander Silvers. Silvers plans to kill the test subjects, so Lian kills him first. When she returns to Elsa, Lian finds her gone.  

Hadden accuses Gabe of lying and corruption. He thinks Gabe murdered Teresa Lipan, but Teresa surprises him by appearing in person. Chance had only injured her, not killed. She describes her first meeting with Gabe during her time as an officer with the Bureau of Alcohol, Tobacco, and Firearms. A group of NSA agents headed by Colonel Silvers were posing as FBI to eradicate a private militia that had recovered data from a government satellite. Gabe, as an Agency operative, saved her life, and helped her when she rescued the wife and son of the militia leader. She left the ATF and joined the Agency. 

Teresa faked her death to find the people behind the Agency. Her investigations into Aramov yielded a connection to Vince Hadden himself. Before Gabe can arrest him, Mara kills Hadden. She and several consortium terrorists take over the Senate building, but Gabe prevents her from detonating any explosives. He chases her onto a train full of hostages, and wounds her, thinking it will do.  

In a post-credits cutscene, Mara escapes later on. Gabe promises he will find her, but for now the Syphon Filter crisis appears to be over since the death of Hadden. Gabe will become the new Agency director, and free it from corruption. Little does he know that an operation is ongoing near the S.S. Lorelei's wreck site. Mara Aramov is recovering the viral crates.

Syphon Filter: The Omega Strain

Following the destruction of the first Syphon Filter virus, the Agency has received a new cover as the International Presidential Consulting Agency, dedicated to battling terrorist enemies. Gabe Logan, as Commander-in-Chief, has hand-picked a team of leaders and agents for his new organization, including Lian, Teresa, Mujari, Dr. E, and more.

The past returns when Syphon Filter reemerges as the deadlier Omega Strain. A Chechen officer named Mikhas Ivankov is selling it on the black market, and outbreaks are occurring around the world. The man behind the conspiracy, Mihai Niculescu, sends Mara Aramov to find and eliminate him. Meanwhile, Gabe and the Agency split up and investigate locations of certain outbreaks.

An Agency team headed by Imani Gray visits Carthage, Michigan in search of Mujari, who disappeared while investigating Dr. Richard Broussard. Broussard had made a deal to give the virus to terrorists from the Anarchiste Liberation Army, but he backed down. The ALA acquired it anyway, and attacked the city. Imani and her team rescue Mujari to find the Omega Strain has infected him. The agents defeat the ALA leaders: Andre Proust, Soren Masson and Jean Fournier, then prepare for their next assignment. Investigating an Ebola outbreak in Uganda with Lian, Gabe shows his obsession for stopping the Syphon Filter conspiracy.

IPCA commander Gary Stoneman tells the Agency operatives about his history as an assassin for the CIA, and how he recently killed mafia leader Dimitri Alexopoulous to keep him from obtaining the Omega Strain in Italy. The team follows Stone to Belarus and tracks a shipment of infected cattle which leads to the residence of Ivankov. They discover that his courier Yuschenko is selling the Omega Strain, and Agency pilot Alima Haddad ends up captured by the Chechens. Stone assumes the worst, presuming she was killed.

Lian later tells the Agency team how she identified that North Koreans were attempting to purchase the virus. She infiltrated the domain of warlord Askar Saydahmat and found his people were about to give the Omega Strain to Sok-ju Yang, with a Yemeni terrorist being present as well. Lian eliminated all the involved parties.

Gabe enlists help from Ehud Ben Zohar of the Israeli Mossad upon determining that Yuschenko plans to sell the virus to Fatha Al-Hassan, a Yemeni leader. Zohar only cares about stopping the man's terrorist connections, so he steals the viral canister after the Agency retrieves it from Yuschenko, and uses it to force Gabe's people into helping his mission.

Zohar and the team enter Al-Hassan's palace disguised as the dead Chechens. After Zohar eliminates Al-Hassan, he searches for evidence of weapons contracts while the Agency personnel defends him. Stone arrives to rescue them, and reveals that Gabe sent him in case Zohar tried any tricks. They exchange the contracts for the virus.

Next, the team investigates a lead recovered from the Belarus operation that shows Dr. Nikolai Jandran is conducting virus tests. Maggie Powers assists them in breaking into Jandran's labs and recording evidence. The team escapes before enemy forces destroy the university where Jandran works.

Mujari, having recovered from the virus, explains his own investigation into the Chechens and why Ivankov wants independence from Russia. He sees that Uri Gregorov and other Russians are imprisoning the rebels, and finds hints of atrocities. Mujari knows both sides have reasons for what they do, thus the situation is not black and white.

Afterwards, Mujari takes control of the Agency team as they check the wreckage of the S.S. Lorelei. The university turned up salvaged boxes, indicating an undersea operation. Mujari requires that his team incapacitate innocent guards, and he evacuates the salvage rig before the Agency's planted nukes destroy the viral containers for good. However, Jandran dies from a serum before he can be brought back for questioning.

While Gabe faces pressure from the president and Alex Birchim of the White House Internal Affairs, he sends Lian and the team to track North Korean agent Yong-jun Kim, a man connected to Murakawa Industries in Japan. The investigation reveals that Murakawa, a part of the Yakuza, was helping to develop the Omega Strain. Aramov arrived before Lian and forced Murakawa to commit suicide for trusting Kim. Kim pretended to work with Murakawa so he could get the virus.

Unfortunately, the team hears tragic news after destroying the Japanese labs. Imani had been tracking Kim on an airplane that crashed in Myanmar. Out of guilt, Lian takes the team to recover her body and the viral sample Kim was carrying. Despite claims that inclement weather brought down the jet, they find evidence indicating that Aramov had paid the Myanmar army to shoot down the plane.

Gabe becomes frustrated with his investigation into the secret corporation Meta Global Funds, which he believes controls the Syphon Filter conspiracy. The purchase of Murakawa Industries by Meta Global was possible through Niculescu Funds, headed by international banker Mihai Niculescu. He is powerful and influential, but secretive as well, so Gabe suspects he is behind Syphon Filter. Against Birchim's commands, Gabe brings the Agency team to the Niculescu Funds headquarters in Zurich. They break in and find evidence linking Birchim to bribes, but nothing implicating Niculescu.

Gabe will later describe the rest of his investigation to the Agency team, and how he looked into Niculescu's Montenegro estate in a final effort to expose him. Although he did not find physical evidence, he learned that Mara was working for him, but Mihai betrayed her. Mara did not want Ivankov to destroy Moscow, for he traded the Omega Strain to the North Koreans for a nuclear weapon.

Having learned of Ivankov's location from Mara, the Agency mobilises to his base and works to prevent the missile's launch. Stone recovers Alima, injured but alive, and the team works with Gabe to disable the nuclear weapon. Ivankov is eventually killed during a fight with Gabe when the enemy attempts to escape through the forest.

Depending on the player's actions, the base is destroyed and the missile launch is prevented, or the nuke detonates in the ocean. However, cutscenes that play show these definite scenarios:

  • Dr. E and Mujari cure the Omega Strain and destroy the final traces of Syphon Filter.
  • Criminals eliminate Niculescu after an Agency computer virus erases the money of his illegal clients.
  • Government officials arrest Birchim after Gabe shows the President files linking Birchim to bribes.
  • The conspiracy is over, and Gabe can focus on other threats.
  • Dr. E resigns from the Agency, confessing that she had met Mihai Niculescu before and had a romantic relationship with him.
  • She intended to kill Jandran as well, believing that her destiny is to change the world.
  • Elsa exits from the Agency base, and Gabe wonders what will happen next.
  • A view of Stone's scope zooming in on Aramov speculates that the former is sent to assassinate the latter in the next game.

Curing the Omega Strain

In order to cure the Omega Strain the player must complete 10 distinct objectives.

  • Carthage, Michigan: Quarantine Zone - Scan tissue samples
  • Carthage, Michigan: Warehouse District - Collect Mujari's recorder
  • Mazyr, Belarus: Krivorozhstal Mill - Acquire tissue sample from cow carcass
  • Mazyr, Belarus: Krivorozhstal Mill - Obtain mill documents from Dobranski's safe
  • Mazyr, Belarus: Belaya Vezha - Acquire sewage sample
  • Sana's, Yemen: Taherir Palace - Obtain Yuschenko's viral container*
  • Minsk, Belarus: International University - Collect Omega Strain serum
  • North Atlantic: Lorelei Salvage Rig - Collect original virus sample
  • Tokyo, Japan: Murukawa Tower - Obtain sample
  • Kiev, Ukraine: Chechen Terrorist Base - Collect Omega Strain DNA code

*This objective does not physically show up in the Statistics screen for Sana'a, Yemen: Taherir Palace. The objective is completed by ensuring that Zohar does not get killed in the mission.

Groups that wanted the virus

  • The Agency
  • Black Baton
  • Chinese Army Rebellion
  • Provisional Irish Republican Army
  • Anarchiste Liberation Army
  • Italian mafia gang
  • North Koreans
  • Yemeni government
  • Red Section


(Dr Nikolai Jandran - Syphon Filter Omega Strain)


  • Syphon Filter is very similar to the FOXDIE virus and the Manticore (which are viruses from the Metal Gear and Call of Duty games respectively) in the sense that they can all be engineered to affect only specific victims and targets.
  • As Lian Xing admitted to Gabe when she was rescued from Rhoemer's catacombs, one must know the specific genetic lock and key for each programmed strain of the virus. Because of this, Syphon Filter has no universal vaccine.
  • As of Logan's Shadow, The Omega Strain is the only game where the player can physically cure the virus by completing a series of objectives. In all the others games in which Syphon Filter is featured, the player is tasked with recovering the antidote in different ways.
  • It appears in the PS4 game Days Gone, as an Easter egg.


  1. Syphon Filter 3 missions, Pugari Gold mine, Pugari Complex
  2. Syphon Filter 3 missions Costa Rican Plantation & Aztec Ruins
  3. Syphon Filter the omega strain, Bellarus special files
  4. Syphon Filter the omega strain, bellarus special video files
  5. Elsa Weissenger, Syphon Filter 2 cutscene, Agency Bio-Labs
  6. Syphon Filter the omega strain, bellarus special video files
  7. Syphon Filter 3, Australian outback
  8. Syphon Filter 2 mission McKenzie Airbase Interior
  9. Syphon Filter 2 cutscene, game beginning
  10. Syphon Filter 2 cutscene, game beginning
  11. Syphon Filter 2 cutscene, game beginning
  12. Syphon Filter 2 cutscene, game beginning
  13. Syphon Filter the omega strain, bellarus special video files
  14. Syphon Filter 2 cutscene, Aljir Prison Escape
  15. Syphon Filter the omega strain, bellarus special video files
  16. Syphon Filter cutscene, Stronghold Catacombs
  17. Syphon Filter the omega strain, bellarus special video files