Resident Evil is set to celebrate its 25th anniversary this year. The series remains one of Capcom's most popular franchises throughout its long history, with numerous games and live-action movies under its belt. Apart from its upcoming anniversary, 2021 is also an important year for the Resident Evil franchise. Numerous projects are expected to launch soon, including Resident Evil 8, a live-action movie reboot, and a Netflix animated series.

Now, as fans wait for the exciting new projects in development for the Resident Evil franchise, let's take a look back at the franchise's main element, the creation of bioweapons. Ever since the first Resident Evil game, the series's conflict has always centered around a corporation that develops viruses, parasites, and other organisms to create bio-organic weapons. From the progenitor virus all the way to the Mold, here is how Resident Evil's viruses and parasites have evolved through the years.

RELATED: 10 Most Anticipated Horror Games of 2021

Resident Evil's Viruses

G Virus Infected William Birkin- Resident Evil Scariest Viruses

During the late 60s, Ozwell E. Spencer, Dr. Edward Ashford, and Dr. James Marcus discovered the Progenitor Virus to create the perfect bioweapon. Although Ashford initially wanted to use the Progenitor Virus' regenerative capabilities to help people with disabilities, it was Marcus and Spencer who wanted to develop the Progenitor Virus as the driving force for their biological weapons project. Since then, the three established the Umbrella Corporation, an organization that led the manufacturing of pharmaceuticals. However, the majority of the company's operations revolved around the illegal development of biological weaponry.

As Umbrella learned more about the Progenitor Virus' potential, the company developed a T-Virus strain, which is undoubtedly the most popular virus in the Resident Evil franchise. The T-Virus and its other strains were responsible for the Spencer Estate and Training Facility outbreak in July of 1998. Still, the biggest destruction it caused was during the Raccoon City Outbreak, which happened in September and October of 1998, killing an estimated 100,000 of the city's residents. The NE-T virus, designed specifically for the Tyrant Project, was also tested during the Raccoon City outbreak.

During Resident Evil 2, Umbrella developed the G-Virus, which is a retrovirus found in the Progenitor family of viruses. The G-Virus was also designed to surpass the T-Virus capabilities, especially since it caused extreme genetic mutations resulting in stronger bioweapons than those the t-Virus has created. The G-Virus's full effects were seen during the transformation of Dr. William Birkin, the creator of the virus, and Curtis Miller as featured in the CGI film Resident Evil Degeneration.

Nemesis an intelligent BOW - Resident Evil T Virus Facts

Another strain of the Progenitor Virus is the t-Veronica virus developed by Dr. Alexia Ashford and is the primary virus featured in Resident Evil: Code Veronica. According to series lore, the T-Veronica virus was developed by synthesizing the Progenitor virus and the gene of a queen ant that contained an "ancient virus." Initially, Alexia administered the t-Veronica virus to her father, Dr. Edward Ashford, but because the infection wasn't controlled, the experiment was deemed a failure. However, Alexia discovered that mutations could be controlled if the subject slowly absorbs the virus via cryogenesis.

After the destruction of Raccoon City as depicted in Resident Evil 3, Umbrella was prosecuted by the government, and in 2004, the company was brought to its end. Despite the Umbrella Corporation's demise, its viruses and combat data collected from both the Mansion and Raccoon City incidents were sold to several other organizations that continued its research. Since then, other viruses have wreaked havoc worldwide, including the t-Abyss virus featured in Resident Evil Revelations, the Uroboros Virus from Resident Evil 5, and the C-Virus as seen in Resident Evil 6. All of the succeeding viruses proved to be stronger and much more controllable than the t-virus and G-virus, especially since infected hosts are much more intelligent, making them the perfect bioweapons.

Resident Evil's Parasites

Although several viruses were the primary cause of the destruction during the Raccoon City incidents, there were also parasites involved in the outbreak. When a host infected by the G-Virus implants its embryos to other hosts that are incompatible with the original carrier's DNA, the embryo will live in the body like a parasite rather than bonding with it. After a short time, the parasite would burst out of the host, making it a threatening bioweapon by itself, given that it doesn't need another host to live. The NE-α Type was also present in Raccoon City. The parasite was used to stabilize Tyrants in the Nemesis Project, which later resulted in creating the Nemesis T-Type, which is a stronger and much more intelligent variant of the Tyrant.

During the wake of Raccoon City's destruction, various organizations were created to combat bioterrorism, hoping that another large-scale outbreak would never happen again. In Resident Evil 4, a new threat was discovered in the form of the Plaga, which is a parasite that causes mutagenic reactions upon the host. Given that the parasite resides in its host's chest, the removal of its head does not kill it but makes the mutation much worse. Like the viruses, other strains of the Plaga were developed to include improvements such as a shorter mutation time and improving the infected's overall strength and agility.

Resident Evil's The Mold

Capcom Resident Evil 7 Eveline Final Form Face

In Resident Evil 7, fans were introduced to the Mold, a fungal superorganism developed by a mysterious organization known as The Connections. Although the Mold was only introduced in the game in 2017, its history dates back to the 1990s as part of The Connections' bioweapons research. The main purpose of the Mold is mind control, allowing a genetically-engineered human to control other people mentally. Throughout the long research period of the Mold, several variants were discovered labeled from A to E types. The most popular type of the Mold is the E-Type, otherwise known as Eveline, who became the primary antagonist in Resident Evil 7. The most astonishing feature of the E-Type mold is its mind control abilities, which the viruses and parasites were never able to do.

most anticipated horror games 2021

Currently, the exact plot of Resident Evil 8 remains a mystery, but it has already been confirmed that it will feature both Ethan Winters and Chris Redfield. The game may delve deeper into the Mold, but it is also possible that a new superorganism will be featured in the upcoming games. From the trailers of Resident Evil 8 released so far, it appears that the game will feature a new enemy-type that resembles a werewolf. Initially, some speculate that the werewolves in Resident Evil 8 are supernatural in nature. While this is a possibility, these werewolves are likely products of either a virus, a parasite, or a new variant of the Mold.

MORE: Chris Redfield in Resident Evil Village Feels Like a Red Herring