Wraiths of Fallen Spirits

Wraiths of Fallen Spirits are malevolent spirits that appear on and outside the Sphere during the events of Prey.

Overview
When Tommy loses all his health, he enters the Death Realm. He must battle the Wraiths of Fallen Spirits to regain both health and spirit energy before returning to his living body. These dishonored spirits inhabiting the realm of the spirit world also seem to inhabit the Sphere. This is probably because their souls are bound to the sphere because of their dishonored deaths at the hands of the Sphere. One of the examples of these wraiths is in a scene where it enters a holding chamber and possesses a child who abruptly is used to brutally murder the other child in the cell.

This is an indication that these wraiths are similar to, if not the same as, demons in other religions, who possess hosts to perform terrible acts of evil. A short time later, possessed children attack on two occasions, including one scene where a school bus is encountered. Also during the level All Fall Down one of Art Bell's caller's daughter showed the characteristics of wraith possession. This means that wraiths started to roam on Earth too. However, these children only appear relatively early in the game and are conspicuously absent for the remainder. The human possession aspect is neither further explored nor resolved, leaving something of a loose end in the plot. However, the Wraiths occasionally appear at various points and fly around, sapping spiritual energy if they come in contact. It's interesting to note that the Sphere Mother, after first seeing a wraith, states that they were not on the Sphere until Tommy's return from his first visit in the spirit realm. Rather than being upset, she instead finds it intriguing.