Golgotha Virus

The G-Virus is a fictional mutagenic virus in the Resident Evil series and the central plot point of Resident Evil 2. It is an advanced strain of the Progenitor Virus with continuous mutagenic properties.

History
The G-virus was first mentioned in Resident Evil 2. According to the game, it had been developed by Umbrella Corporation scientist William Birkin, who had also done pioneering work on the T-Virus.

Further information on the G-virus was released in the form of a fictional report made by Albert Wesker. According to "Wesker's Report II," a primitive form of the virus was discovered in the mutated body of Lisa Trevor, on whom the Umbrella Corporation had been conducting unethical genetic and viral experiments for two decades. When she displayed unexpected immune resistance to the experimental NE-α parasite, Birkin and other researchers looked for a cause and found what would later become the G-virus.

Although the name was never stated, it is widely believed that the G stands for God. The reasoning behind this is because it works so fast and is spread through procreation rather than infection like the T-Virus; additionally, considering William Birkin's whole personality and demeanour towards it, it is a feasible assumption to believe he thought his creation was indeed, a God.

Characteristics of the G-Virus
The G-Virus, shown as a purple, aqueous liquid in a glass vial in Resident Evil 2, greatly increases the carrier's metabolism, accelerating cell duplication and revitalization of dead cells at the cost of higher brain function by continual destruction of mitochondria in neurons, causing the infected person to degrade to sub-human levels. The carrier exhibits animalistic behavior, loss of moral reasoning and becomes driven by self-preservation. Ultimately, carriers become creatures simply dubbed G.

Flaws of the G-Virus
Beyond these qualities, the mutations induced by the virus tend to be extremely volatile. The only known host was William Birkin, who injected himself with the virus after being mortally wounded by the Umbrella Special Forces Unit attempting to recover the G-Virus from his labs. Unlike T-Virus hosts, G-Virus hosts never stop mutating, even without external stimuli, thus causing transformations akin to a sort of artificial evolution or the like. G-carriers evolve even faster when wounded, due to the incredible regenerative capabilities of infected cells.

William Birkin undergoes five distinct stages of transformation throughout the game, and it is most likely other G-carriers would also undergo similar stages, although the unpredictable nature of G-Virus mutations means that the details would differ.

Stages
Stage 1 bears the greatest resemblance to the host, though its upper torso is far more muscular due to a sudden increase of muscle mass. The right arm, where Birkin was sprayed with several sub-machinegun rounds, is considerably swollen with muscle, (this may be due to the uncontrollable cellular reproduction that trademarks all viruses developed as derivatives of the Progenitor Virus) and a large tumor-like eyeball has developed within the shoulder; this is supposedely where the G-embryos are developed prior to oral implantation into a potential host. As this form does not possess any natural weapons (claws, fangs) with which to attack its foes, G instead makes use of its superhuman strength to tear a pipe from a guardrail to swing about and attack with.

Conversely, when Annette recollects William Birkin's transformation and his slaughter of the Umbrella Special Forces, G is shown slashing the soldiers with talons. When G first appears, though, no such claws are visible whatsoever thus one can assume that the talons were either lost in a process of devolution (contrary to the G-Virus's properties) or atrophied away following lack of use in any further combat.

The advent of Stage 2 results in the carrier's visage and remains of its skull descending into the anterior of the thoracic cavity whilst the digits of the right hand sprout into massive talons comprised of bone. Two tiny, vestigial limbs also develop lateral to the abdomen underneath the original arms and a new rudimentary skull grows to take the place of the former; it is in this new cranium that an entirely new brain, far more animalistic and vicious, is created as a result of the transformation, replacing Birkin's true brain. This form is the first one to attack openly with its claws, and has a much higher offensive power than its first stage.

Stage 3 is perhaps the least grotesque of the various forms that William Birkin assumes following the injection of the G-Virus into his body. The host by now has shed all of its integument-like skin, revealing its musculature, whilst hundreds of spike-like projections rise prominently into an apex from a point in its upper left thorax; the visage of William Birkin, on the other hand, slowly begins to merge and fade away into the abdomen. In addition to its right hand, the beast's left hand also possesses deadly talons now; in fact, the abomination has grown in height thus its primary arms have also elongated beyond normal human proportions. The vestigial arms of the prior stage, meanwhile, have also matured into functional limbs with talons and the rudimentary head now sports a lipless grin, bearing its razor sharp teeth, that vaguely resembles a skinless form of the facial features of the Nemesis. Finally, a secondary, smaller eyeball-like tumor has developed in the left rectus femoris of the creature. This form is the only one that has bilateral symmetry, and to some, it resembles a demon in appearance.

Furthermore, when G is encountered after crashing through the ceiling shortly before its complete transformation into its hexapodal fourth form, the appearance of its third form has changed slightly. The spikes located on its chest have begun to open thus hinting to its fourth form.

Stage 4 involves the host mutating from a standing equilibrium as a bipedal to a hexapodal base on the ground involving the utilization of its four primary limbs to maintain movement. The skull and maxilla of the creature have elongated to accommodate its massive mandible, a gaping, circular cavity surrounded by rows of spike-like projections, which has now fused into the thorax of the beast. Despite its appearance, however, this stage of G is extremely agile, able to sprint and leap all about a room with ease, and the aforementioned spikes around the mouth are more than capable of impaling its prey with extreme ease, given the superior agility and speed of the stage.

Stage 5 is by far the most grotesque of all the forms that G has mutated into. After extreme physical trauma to G, it has become a shapeless blob of flesh, spikes, and tentacles, slowly dragging itself via attachment of its largest tentacles to a stationary object and subsequent use of its lesser tentacles to slime forth, an appearance that evokes vividly H.P. Lovecraft's description of a Shoggoth. It appears that by this stage, the G-Virus has evolved continually by merging with the beings it has devoured to sustain itself; this is evident as one can discern various zombies and other lifeforms protruding from the trunk of the creature. This final form was killed only after the train which it had invaded was consumed by a massive explosion following the automatic activation of its self-destruct sequence, as the damage it had sustained at cellular level was too high for even the G-Virus to counteract.

Since the G-Virus infected William Birkin was killed at this point, it is unknown if it would have continued to mutate into further forms.

Means of infection
Infection by the G-Virus is caused by injection or ingestion of the virus, but unlike creatures infected with the T-Virus, G-mutants cannot pass infection on to other creatures through physical contact or injury. Instead, they create offspring by orally implanting small, parasitic organisms into a live host through the palm of the hand, in the case of William Birkin. In unfortunate cases, a host who has no compatible DNA match will reject the parasite in a matter of hours or less. The embryo rapidly grows inside its host before bursting from their chest (an apparent homage to the Alien movie series). Upon exiting the host body, the embryo quickly mutates into its adult form and goes in search of another host.

Within Resident Evil 2, the G-Virus rejected embryo is encountered in the sewers, following its rejection from a genetically dissimilar host, commonly called a G-Imago; it was a large, slow creature devoid of flesh that possessed with an elongated neck and seemingly stood hunched over; this was due to the fact that the right side of its body was vastly disproportionate in comparison to its left region, as a result of unequal bilateral symmetry, which conversely was a result of its cellular instability by the uncontrolled merging of the virus with two different DNAs. The creature also periodically vomited G-Embryos which would cling to the opponent in an attempt to disorient him as the G-Imago attacked.

The G-Imago found in Resident Evil Outbreak above the subterranean Umbrella laboratories, after bursting forth from Monica's body, likewise, possessed similar features such as an elongated neck, exposed muscle tissue, and the ability to spawn G-Embryos; its body also lacked bilateral symmetry as evident by the fact that its left arm is smaller than its right. As opposed to the G-Imago in the sewers, this offspring is quite tall and possesses a large sac on its dorsal cavity covered with bullas in addition to a tail.

A DNA match can only be achieved by a blood relative of a G-mutant becoming impregnated. The embryo begins to pupate and assimilate the host body, turning them into what can only be assumed to be a mutant of immense strength. Sherry Birkin was infected by her father, but the infection was stopped with an experimental anti-G-Virus vaccine, codenamed DEVIL, before mutation could occur with help from her mother Annette Birkin and Claire Redfield. It must be noted, however, that DEVIL did not destroy the cells infected with the G-Virus, it merely halted its spread through Sherry's body; thus, Sherry still has viable samples of the virus within her system. Also, the antivirus was administered in a time that may range from twenty minutes to more than two hours later. Given the rapid-acting powers of the G-Virus, it is unlikely it could not have already been absorbed into Sherry's body.

Differences from the T-Virus
The G-Virus is quite different to the T-Virus in terms of action and transmission. While both viruses have the characteristic of inciting mutation in infected organisms, the similarities end there. The G-Virus has none of the necrotic properties of the T-Virus, and as such, host organisms do not decompose (the characteristic rotting of the zombies).

The G-Virus is also far less virulent than the T-Virus, for while the T-Virus can be transmitted by body fluids, direct attack from an infected organism, or even water, the G-Virus can only be transmitted by direct injection or active impregnation of a parasite into the prospective host by a G-mutant, and G-mutants (as evident by Birkin and his spawn) instinctively attempt to reproduce as any other animal species. In this manner, G-Virus hosts act much more like living creatures than those infected with the T-Virus; while T-Virus infection can be considered accidental (as the host does not actually mean to infect its victim), G-mutants actively attempt to perpetuate their species. This has the frightening implication that, while the T-Virus is infinitely more contagious, a G-Virus epidemic would be uncontrollable and actively hostile to humanity, as G-mutants would seek to reproduce over any other instinct.

The G-Virus also acts exponentially faster than the T-Virus, with William Birkin manifesting considerable physical mutation mere seconds after infection. Apparently, direct injection of the virus is incurable, as it acts too quickly for a vaccine to be effective. Infection by parasitic impregnation, however, can be controlled much like the T-Virus, with a vaccine being effective if administered during the initial stages of infection, before the embryo can gestate. While the T-Virus' effects on long term, controlled exposure are well documented, Tyrant, the Hunters and the Lickers for instance, the effects of such exposure to the G-Virus are unknown, as there was no testing in this field done before the Raccoon City incident. However, results of such manipulation of the virus COULD be seen in future sequels of the series, considering both HUNK and Ada Wong were able to procure samples of the virus for Umbrella and Albert Wesker, respectively. However, if the effect of said exposure was similar to the T-Virus and T-Veronica virus, such organisms would theoretically be the absolute deadliest creatures ever made by Umbrella. Birkin himself, an accidental G-mutant, was more powerful and deadly than any creature created with the T-Virus on purpose. The effects of the G-Virus on non-human hosts is unknown, but they are probably just as radically powerful and unstable as their human counterparts in comparison to the T-Virus.