Corruption virus

Unknown Simple Life Form 2 is a Phazon-based virus described in Metroid Prime 3: Corruption. It is said to have infected Aurora Units, and seems to have also been used by Dark Samus to infect Samus Aran, Rundas, Ghor, and Gandrayda. It is implied that the depiction on the title screen may be the virus, similarly to how Metroid Prime depicted Metroid nuclei.