An Inferius (plural: Inferi) is a corpse controlled through a Dark wizard's spells. An Inferius is not alive, but a dead body that has been bewitched into acting like a puppet for the witch or wizard; this manifests itself as a white mist in the controlled corpse's eyes. They cannot think for themselves: they are created to perform a specific duty assigned by the Dark wizard who commands them, and as seen in the Inferi guarding Voldemort's Horcrux in a seaside cave, remain idle until their task can be performed. This task is then thoughtlessly carried out, whether or not it will produce any result. Inferi are difficult to harm by magic; however, they can be repelled by fire or any other forms of heat or light, as the Inferi in Voldemort's cave had never been exposed to either of these elements. When defeated, they return to their idle state.