[Name] NE-Alpha Parasite [Source] Resident Evil 3 [Symptoms] 
The NE-Alpha, or Nemesis Alpha, Parasite has an immunity to the T-virus, and is used to protect the higher brain functions of B.O.W.'s. However, if the B.O.W. is incompatible with the parasite, they die inside of twenty minutes. If they are compatible, however, the parasite acts as a second brain, taking over the functions mof the T-virus ravaged host brain. The host increases in size and strength; and become hardy enough to survive multiple gunshot wounds. The parasite's tentacles become threaded throughout the host's entire body; and can be utilized as a weapon.