Beginning in 1927, the Chimera began their attack on Russia. From the very beginning Russia's military was inefficient in combating the alien threat, especially in having human soldiers being vulnerable to the Chimeran virus. Russian scientist Dr. Fyodor Malikov worked on using Pure Chimeran DNA that he had discovered from the site of the Tunguska Event and created an experimental vaccine which shows promise in creating a resistance to the virus. The Russian government, desperate to stem the Chimeran tide, ordered many surviving soldiers to be vaccinated with Dr. Malikov's vaccine. The experiment initially worked, as the soldiers demonstrate a strong resistance to the Chimeran virus and were more effective in fighting the Chimera. However, some soldiers began to exhibit erratic and violent