(Capcom's primary storyline)
"They are incredibly intelligent. And are capable of mutating in response to injury."
— Finn, reading a report
J'avo (ジュアヴォ Juavo ) are a class of mutant humans created from the injection of C-Virus into the bloodstream. Unlike the Zombies, created by inhaling fumes loaded with C-Virus, J'avo maintains their intelligence. The name, J'avo, and the names of their various mutations are derived from Serbian words as decided by the BSAA European branch's R&D department. In Serbian, the word đavo means "devil".
Unlike earlier strains such as the one which infected Bindi Bergara during Neo Umbrella's testing, the strain of C-Virus which saw widespread in the 2012 and 2013 terror attacks robbed the infected of their free will and made them intensely loyal to Carla Radames. Another modified strain may have been used for J'avo soldiers of Neo-Umbrella, who have been observed to mutate at will rather than as an automatic response to injury.
In appearance, J'avo maintain an identifiable human form, though significant differences can be seen on a closer inspection. Most noticeably, J'avo mutates to have multiple eyes, usually scattered asymmetrically across the face and forehead. There is no specific pattern to the eye positions, and eyes are of different sizes with as many as four small eyes positioned around large ones. The eye color themselves vary from an off-white or pale yellow to a darker yellow or brown. The emergence of new eyes causes damage to the face and may result in bleeding. Elsewhere on the face, the skin is noticeably discolored and veins become more prominent. J'avo teeth are seen to be uneven, jagged and discolored.
Mentally, J'avo kept their higher brain functions though maintain the aggressive tendencies of victims of other viruses such as t-Virus. J'avo groups are known to work together to kill uninfected people and can communicate verbally as well as they could before infection. Martial skills are also unaffected, meaning soldiers or militia fighters are just as skilled post-infection.
J'avo, even in their base form, are incredibly powerful. With one hand a J'avo is capable of lifting an adult human off the ground.
Their regenerative abilities are quite adept, as are their tolerance of pain, being able to receive injuries that would cripple or outright kill normal humans.
One J'avo was shown to survive having the entire upper half of its skull blown off. After kneeling on the ground for a moment, its head regenerated, standing and resuming its fight against BSAA agents.
As with other C-Virus infected, J'avo body temperature is higher than that of humans, the more it must heal itself in response to harm, the hotter its body shall become.
For this reason, when a J'avo finally succumbs to its wounds, its body shall disintegrate in a brief but dazzling flash of sparkling flames.
All J'avo demonstrate highly effective regenerative capabilities. They are able to completely heal heavily damaged limbs, muscle-tissue, and skin in mere moments. These regenerative capabilities, however, have the tendency of being extremely erratic and can cause spontaneous mutations depending on where the J'avo was damaged. Interestingly, a J'avo is not limited to one mutation. It is possible for the same J'avo to experience multiple mutations such as a combination of a Noga-Let and the Ruka-Srp or the Noga-Oklop and the Ruka-Bedem. It is unknown what other combinations are possible. Special J'avo working directly with Neo-Umbrella displayed the ability to mutate at will due to the strain that's been used. The head Glava mutations seem to cause the J'avo to lose their intelligence, as their attacks become more animalistic.
|Glava-Sluz||Head||This mutation is triggered when the J'avo suffers heavy damage to the head. The creature spits a sticky, viscous fluid akin to webbing to constrain the player that can leave them vulnerable to other attacks whilst they try to free themselves. The name means "Head-Slime" in Serbian.|
|Glava-Smech||Head||When the head is damaged enough, the J'avo will mutate in this manner. It appears the torso ruptures open, causing the beetle-like mandibles to extend. The mutated creature will use these mandibles to pick a player up into the air and either bisect them or devour them like an insect. The name could possibly translate to "Head-Laughter".|
|Glava-Begunats||Head||This variant comes from the head as the J'avo regenerates damage. Two different protrusions appear, one resembling the front/head of a cicada, the other containing two small hook-like appendages. This type of mutation is very dangerous, as this mutation causes the J'avo to enter a berserk frenzy and will viciously attack the player until it is dead. The name could translate to "Head-Runner" or "Runaway head" from Serbian.|
|Glava-Dim||Head||This mutation seems to come from the head. Several protrusions come in place as the J'avo regenerations, including something that resembles the stinger and abdomen of a bee or wasp or some sort. The creature emits a poisonous gas that damages and impairs vision. The name translates to "Head-Smoker"/"Head-Smoke"|
|Ruka-Srp||Arm||The arm extends between the joints, causing the length to increase greatly as the hand mutates into a crude and brutal sickle. The end result is a limb that greatly resembles the arms of a praying mantis in the way it folds. Also can combine with Ruka-Bedem to form a deadly shield/sword combo. The name could possibly translate to "Sickle arm".|
|Ruka-Khvatanje||Arm||The limb becomes more rounded, longer, and wider. It ends with three pincers that are capable of grappling a person. The newly mutated arm is able to stretch over great distances, bend around corners, and reach over cover. The name could possibly translate to "Arm to grab"/"catcher arm". or "Arm-Capture"|
|Ruka-Bedem||Arm||The arm ruptures and splits apart as additional organic material grows. Thick muscle tissue covers the gaps from where the sections of the arm extend. The outside of the limb becomes covered with layered pieces of armor. The J'avo will use this armor to shield their head and body from damage. Also can combine with Ruka-Srp to form a deadly shield/sword combo. The name means "Arm-Wall".|
|Noga-Trchanje||Leg||Sprouting from the back, a new abdomen and thorax resembling that of an insect's replaces the legs and leaves the upper body dangling. This form of mutated J'avo seems to primarily move and attack by pouncing. The name translated from Serbian as "Leg-Work"|
|Noga-Let||Leg||The lower torso explodes, causing a moth-like body to erupt. A pair of large wings, capable of carrying the human torso, appear as well as a long-tailed stinger that is capable of piercing an unwary target. The name translates to "Leg-Flight"|
|Noga-Skakanje||Leg||As the legs rupture, a new lower body grows in its place resembling an insect's thorax and abdomen, complete with large insect legs that are easily able to carry the weight of the J'avo and kick a player. The name could possibly translate to "Leg-hopper"/"Leg-Jumps"|
|Noga-Oklop||Leg||The legs of the J'avo split and expand as they mutate. This ends with the upper-body being carried by a pair of legs covered with insect-like carapace with some human bones protruding. The new legs enable them to perform powerful jumping kicks that can knock a target down. The name translates as "Leg-Armor"|
|Telo-Eksplozija||Torso||This mutation causes the J'avo's torso to mutate into a grotesque cocoon. This mutation has no attacks and simply tries to get as close to you as possible. Upon death, it will explode and damage anything in the vicinity. If shot in the legs, it will kneel over and explode in place. The name translates as "Body-Explosions"|
|Telo-Krljusht||Torso||The J'avo encases its torso in scales that render its body immune to gunfire though it is still vulnerable to melee attacks and explosions. The name translates as "Body-Scale"|
|Telo-Magla||Torso||The J'avo writhes on the ground and sprouts several appendages and what appear to be moth wings though it is incapable of movement once it has transformed. This mutation will constantly emit a poisonous gas until it is destroyed. The name translates as "Body-Mist"|
|Chrysalid||Varied||This mutation can occur randomly whenever a J'avo is damaged, causing it to enter a stasis inside of a cocoon. The transformed creature that erupts from the cocoon can vary widely.|
For all intents and purposes, in the sense of mentality, J'avo have a human level of intelligence. They will use firearms (sub-machine guns, sniper rifles, rocket launchers), will signal to each other and make use of communication and tactics to take out their enemies. If a J'avo has no means of long-range attack, they may attempt to hold on to a target to give one of their allies a chance to attack. If they have the training, they can even commandeer tanks, trucks, attack helicopters, and jets, as any trained soldier in those branches could. Many prefer to fight on foot, however; some J'avo will instead use close-range weapons, namely machetes and combat knives. They are extremely persistent and incredibly aggressive.
One of the most dangerous aspects of the J'avo comes from their spontaneous mutations upon injury. There is essentially no truly safe spot to injure a J'avo at some points as anything can trigger a certain mutation, which could lead to severely worsening a situation. Their mutations are extremely dangerous and deadly when combined with their intelligent coordination. The only thing that should be more worrisome than their mutations is their evolution into a Chrysalid. In this pod-like state, the J'avo is vulnerable but when it hatches they become substantially more deadly.
(Sometimes even using high-powered rounds can cause immediate cocooning. Although "Telo" mutations are much rarer outside of Edonia and Neo-Umbrella levels.)