Capcom Database

Tyrant Virus, otherwise known as the T-Virus, is a fictional virsus in the Resident Evil franchise. It is the general name given to a series of mutant Progenitor virus strains. Initially developed by Umbrella Pharmaceuticals in the late 1960s, the primary goal of the "T-Virus Project" was to effectively eliminate the need for a large-scale conventional army and generate revenue to go to their eugenics program, the Wesker Project. This required two things: the virus had to be highly-contagious to the point of infecting an entire target population and guarantee a 100% mortality rate. Such a virus was impossible due to such contagions' tendencies to kill too many people at once and prevent further spread.

By 1978, development moved from creating a lethal, highly-contagious virus to one that would mutate hosts to become physically stronger and remain alive despite organ failures and severe brain damage, the latter leading to murderous aggression and an obsessive hunger to the state of cannibalism. In the mid-1980s, the T-Virus Project focused on creating intelligent bio-weapons, most famously the Tyrants.


The T-Virus is capable of various methods of subject infection. Research files supplied in the Arklay Laboratory identify the virus as having a protein structure.

  • Injection: Due to its importance in bio-weapons development, the direct injection of the virus into an organism's body was considered by Umbrella to be the "primary" means of infection.
  • Water: Arklay Dam and the Raccoon Sewage Treatment Plant were contaminated with the virus, leaking into the city's water supply as a result and infecting many civilians.
  • Direct Fluidic Transmission: Anyone attacked by an infected host in close combat, be it by bite, scratch, gash, or stab may have the virus transferred to their bloodstream via contact with infected bodily fluids and tissues. Umbrella Corp. believes this to be a

secondary means of infection. It is not a precise form of infection, however, as dry bites are a possibility.

  • Airborne:: Evidence in the Arklay Laboratory and the Military Training Center indicates the T-Virus is capable of spreading as an airborne pathogen in unspecified laboratory conditions.


Different T-Viruses can react in different ways to humans. Before 1978, the t-Virus simply killed people, but the independent accomplishments of Marcus' and Spencer's labs led to zombification as the typical outcome of infection. Higher brain functions among the infected almost cease entirely and zombies can only perform minor tasks such as turning doorknobs.

It should be noted that while zombification is known to result in brain damage and necrosis, the hosts are not, in fact, dead, as the T-Virus is incapable of reanimating dead tissue. Even with a shut down of the respiratory and cardiovascular systems, or apparent brain death, infected people do not die. Since some of the traits of zombies are the decomposed skin and the lack of pulse, they are often mistaken for reanimated corpses.

In viral strains capable of the "V-ACT" process, unconscious zombies are known to mutate in an hour or so. Crimson Heads develop razor-sharp claws, sharp canine teeth and their hearts pump blood rapidly across the body, resulting in their crimson hue. Other strains instead create "Lickers", which are humans whose skin has entirely rotted away to show the muscles. Their brains are exposed, and they have powerful, long tongues that can be used as whips to attack people. An oddity of V-ACT is a creature known as "Suspended". Only one specimen of this creature is known to have existed. What it actually was is unknown, though it is possible to have been the result of a zombie ceasing its mutation mid-transformation.

There are rare cases where a human responds differently to T-Virus infection and transforms into a dominant mutant. These mutations are the result of unique genetic factors that only one in ten million people displays. People with this genetic quality were highly prized by Umbrella, as they could be turned into bio-weapons known as Tyrants.