The G-Virus is a fictional virus from the video game series Resident Evil, created by Capcom. It is known for its ability to mutate living organisms, enhancing their physical abilities and intelligence. The virus was developed by the Umbrella Corporation as part of their bioweapons research, leading to catastrophic consequences. In the storyline, the G-Virus infects individuals, transforming them into powerful creatures called G-Adults. The primary antagonist associated with the G-Virus is William Birkin, a scientist who injects himself with the virus to gain its powers. This transformation results in a series of monstrous forms, posing significant threats to the game's protagonists.