The Nemesis Parasite:
The Nemesis Parasite is the least known of Umbrella's genetic researach. It was only ever mentioned in Wesker's Report II. Because of the name, it is led to believe that the Nemesis Tyrant was created with it. The Nemesis Parasite wouldn't be a virus by itself, but rather a host for the T-virus, infusing it into the body. Because of this middle-man that would be the original Nemesis, it would dictate the path of mutation.
There are no other known creatures associated with the Nemesis parasite, although it seems that Lisa Trevor was infused with it, as well. Reports show that her body actually miraculously absorbed the parasite, which is probably due to the cess pool like state of her system. The Nemesis shares properties with the standard Tyrant, including strength and height. Although, the Nemesis shows superior speed and intelligence, and even retains the base skill in speech, although such skills are very limited. The Nemesis is also clothed, so this could mean that the genitals are external rather than the internal genitals of the Series One Tyrants. The Tyrant Mr. X from Resident Evil 2 is more than likely an early form of the Nemesis. The Nemesis shows properties of necrosis in its face that are similar to zombies rather than the smoothness of the Tyrants. The lips are receeded from the teeth to give a skeletal appearance, and the eyes are milked over. The Nemesis shows mutative properties, and they are slower than the G-virus, showing it is in the T-virus family.
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