The C-Virus was created by combining an enhanced version of the Veronica virus with the G-virus variant within Sherry Birkin's blood. Unlike the t-Virus, the C-Virus allows the infected to maintain some of its intelligence, allowing the creatures that mutate from the virus to co-ordinate attacks and use weapons. An enhanced version of the C-Virus was engineered, but only three syringes containing it are known of — all three used before the end of the Lanshiang conflict. Carla Radames is the only one who knows how to produce it.