Typically, exposure to Tiberium is fatal to any lifeform (save for the Scrin, who in fact thrive in Tiberium). However, victims of this exposure will instead mutate on occasion. Mutations are not exclusive to survivors of Tiberium radiation, as is the case of the Visceroids. These creatures are blob-like masses of flesh extremely erratic in behaviour. Generally any living thing killed by Tiberium radiation or Tiberium-based weaponry can potentially mutate into a Visceroid. During the first and second Tiberium Wars, Visceroids had a very unstable blob-like appearance, constantly shifting body structure and even fusing together to form larger Visceroids. By the third Tiberium War, Visceroids appear to have stabilised physically, sprouting three limbs to support and mobilise itself.
Visceroids are typically found in any location where Tiberium is present and will actively attack anything they find, living or otherwise. They attack by spraying a Tiberium-based gas capable of converting victims into more Visceroids with enough exposure. Visceroids are also rapidly healed by further Tiberium exposure. By the fourth Tiberium War, the Forgotten had started to domesticate Visceroids, using them as suicide bombers or even farming them for food.
