The cruciforms are symbiotic entities found on the walls of the labyrinthine caves of the planet Hyperion.
Cruciforms resemble in shape and proportion the crucifixes that are central to the human religion of Christianity. Their texture is similar to that of soft coral, and they give off a bioluminescent pinkish glow. Their back surfaces are entirely flat and smooth, lacking any obvious adhesive properties, and a set of knobs on the top "arm" of the cruciform allow them to be easily tied to necklaces and lanyards.
After being placed on the skin of a host, the parasite grows root-like fibers throughout the body, and copies the DNA and memory samples from the host; after growing into a host, the cruciform shares its host's DNA.
After the accidental or natural death of the host, the parasite is able to recreate the host's body and mind, repairing bodily damage and thus resurrecting the individual. Only the tiniest fragment of host tissue and cruciform matter remains is required to regenerate both host and cruciform. The procedure is not flawless; memory and mental capabilities are lost with each consecutive resurrection, and the body slowly changes to a neutered, stunted form.
Once a cruciform bonds to a host, it is impossible to remove through surgical or other conventional means. There are only three known ways to remove a cruciform from a host body:
- By subjecting the body to sustained immolation over the course of numerous resurrections, so that the body is weakened enough for the cruciform to be removed,
- By having the Shrike remove a cruciform manually from a body,
- By having the host become infected by the Aenea virus.
The cruciforms were created by the TechnoCore UI in the far future in order to keep a population of humans alive so that their brains could serve as a network of biological computers for the TechnoCore. For this reason the cruciforms were bred in the planetwide labyrinth of Hyperion and sent backward in time.
The Bikura, an indigenous tribe of humanoids native to Hyperion, originated as a group of settlers who encountered the cruciforms, degrading over time due to repeated resurrections into physically and mentally stunted versions of their former selves.
Discovery by the modern Hegemony
The first modern human to encounter the cruciforms was Father Paul Dure, on the morning of day 111 of his exile to Hyperion. Father Dure had discovered the Basilica beneath the Bikura's camp on day 105 and was planning his return to spread the news of his discovery when the Bikura discovered that he was not "of the cruciform". They subsequently led Father Dure to the base of the Cleft where he discovered an entrance to Hyperion's labyrinth and the cruciforms that lay inside.