The Leech or "Hill" was a kind of giant leech selectively bred by Dr. James Marcus that proved influential in the development of the Progenitor virus and t-virus and was the main creature which Marcus experimented on, having evolved in ways previously unthinkable, overcoming the confines of annelids. Over the course of the Raccoon City outbreak which superseded the initial leech attack, two sources of leeches emerged with notably different species being infected with the t-virus. 1 2
History
During his attempts to improve upon the Progenitor virus' ability as a weapon, Dr. James Marcus conducted experiments on leech specimens. The specimens exhibited a hive-mind brought on by the virus' infection, and soon captured Marcus' attention completely. Using Progenitor as a base, Marcus combined the virus with the DNA of his leeches, resulting in the creation of the t-virus.
Using the leeches natural instincts, Marcus was able to utilize the blood sucking nature of the leech to spread the t-virus in the Raccoon Forest. Under the guidance of the Queen Leech, the Leeches attacked the Ecliptic Express which began the biohazard outbreak in 1998. The Management Training Facility, Arklay Research Facility, Arklay Treatment Plant and Underground Research Facility were also attacked. It is presumed that the leeches were wiped out following the self-destruction of each of these facilities. 3
Attributes
In their t-virus or Progenitor infected state, the leeches are extremely violent and will cease at nothing to take down prey, utilizing a hive-mind and attacking in groups. Due to their blood-sucking nature, they are extremely capable of transmitting the t-virus and infecting other beings. The Queen Leech utilized this ability in order to spread the t-virus throughout key Umbrella facilities. It has an extremely large mouth which common leeches do not possess that has been further enlarged by the virus which is utilized for both sucking blood and biting away at flesh, causing severe injury and being able to consume a human being whole within a few minutes when attacking as a group. Due to the high concentration of the t-virus in their body fluid which is injected into their prey during hunting, the chances of transmitting the virus are very high. They have a special receptor-like organ which acts as an "eye" on their back. 4
In the beginning of their growth as documented by Marcus in his Leech Growth Records, the leeches start off simply as parasites and predators. Within a manner of days, they double their size and overall numbers, as their eggs hatch within a mere hour. Like other animals infected with the t-virus, they have ravenous appetites, and in early stages, will resort to cannibalism to sustain themselves. Along with their overall size, their mouths also enlarge, allowing them to feed on larger prey. When in groups, they can infuse together to form a humanoid life-form known as "Mimicry Marcus".
Secondary Infection
Marcus's leeches were not the only leeches that became infected with the t-virus. Whilst the developed leeches showed considerably more intelligence than the secondary infected leeches, they proved to be verarcious hunters nevertheless. The first recorded sighting stems from the Raccoon General Hospital where vast hoards of leeches dwelled. Never acting in quite the same unilateral appraoch witnessed with the Mimicry Marcus, these leeches instead opted to infect a human lifeform and attach themselves to that body. This created the Leech Man. These leeches however were not the same species developed by Dr. Marcus, and are extremely vulnerable to high levels of heat. 5
The second sighting of secondary infected leeches occurred in Raccoon University. Many leeches had gathered in the depth of the basements, away from direct sunlight that would dehydrate their skin.
Footnotes
- 1. Leech Notes
- 2. Biohazard: The Umbrella Chronicles Official Guidebook ~ page 041
- 3. Resident Evil Archives ~ page 182
- 4. Biohazard 0 Kaitaishinsho ~ page 061
- 5. Investigation Request