 SCP-742 is a retrovirus, approximately times more complex than any known naturally-occurring virus. SCP-742 infects all cell types, but initially only enters the light-excicle and helper T cells, leading to a state of immuno-compromise that allows SCP-742 to infect every one of the infected subject's cells. T cells secrete hormones that increase appetite, as well as a signal compound. Once full infection is achieved, concentration of this signal compound reaches a target level, and the infection enters stage 2. SCP-742 affects the nervous system, causing the infected subject to ravenously consume large quantities of protein-rich food, and then seek a dark, secluded area. In a cave, abandoned building, or crypt.