Possessed

Possessed Chaos Space Marines are those individual who have forsaken their humanity and given up their souls and bodies to the Chaos Gods. Their body is then possessed by a Chaos Daemon, who keeps its human shell alive with the energy of the Warp. Possessed Chaos Space Marines feel no pain and their bodies can be warped and mutated to suit the purpose or whim of the Daemon that inhabits them.

History
For some Chaos Space Marines, simply dedicating their souls to the service of the Ruinous Powers is not enough. Motivated by either a deep devotion to their infernal masters or an unquenchable thirst for power at any time, some will offer themselves wholly to Chaos, becoming willing hosts to the immaterial entities of the Warp. Such possession is a lengthy and agonising experience, as the Daemons within them manifest their physical forms, changing it to better suit their particular tastes. Those who offer themselves up for possession spend months in rituals of purification, offering up sacrifices and preparing their bodies to harbour a particular entity. Though the personalities of those supplicants are abandoned forever, many possessions are nonetheless great celebrations of the union between the normal and the daemonic. They are marked by their kindred with orgiastic feasting and depravity and by the devout with blasphemous hymnals of impurity.

The origins of the first Possessed Chaos Space Marines can be traced back to the middle years of the Great Crusade sometime during the 30th Millennium. The entirety of the Word Bearers Legion and their Primarch Lorgar were formally rebuked by the Emperor of Mankind for their desire to worship him as a deity contrary to proscribed tenets of the Imperial Truth, the secular, rationalist, philosophical and cultural beliefs promulgated by the Emperor during his Great Crusade to reunite all the worlds of Mankind beneath the umbrella of the newborn Imperium of Man. This collection of beliefs upheld the core values of reason, science and secular progress over older traditions of religion, superstition and faith that had longed defined many of the human worlds that had fallen into darkness during the Age of Strife after the fall of humanity's first interstellar civilisation. The Emperor himself declared that Mankind would never be free to progress and advance to its destined position as the pre-eminent intelligent species in the Milky Way Galaxy until churches, idol worship and superstition were swept aside.

After being formally chastised and humiliated, Lorgar, on the advice of his First Captain Kor Phaeron and the Word Bearers' First Chaplain Erebus, both secret devotees of the Chaos Gods, decided to undertake a Pilgrimage to discover if the Gods worshipped by the adherents of the ancient Old Faith of Colchis were real and worthy of the Word Bearers' faith and allegiance. Lorgar believed that the Emperor was wrong to condemn Mankind's natural instinct to seek out the divine as an unworthy superstition and he intended to discover if there were truly deities worthy of humanity's respect. To this end, though Lorgar no longer had any love or loyalty for the Emperor, he and his XVII Legion rejoined the Great Crusade but did so only so their efforts could serve as a front for their pursuit of what came to be known as the Pilgrimage of Lorgar. The Primarch journeyed with his Word Bearers Legion's Chapter of the Serrated Sun to what was then the fringes of known Imperial space.

It would be in the Cadia System that Lorgar would learn that his suspicions had been correct and that the shape of all of the religions across the galaxy that possessed so many similarities to the Colchisian Old Faith were not artefacts of Mankind's collective unconsciousness, but expressions of worship in the universal truth that was Chaos. Discovering the world of Cadia, a Word Bearers landing party, led by Lorgar, was greeted by a large number of barbaric human tribes that showed little fear. The Word Bearers eagerly approached the natives. A strange woman emerged from the crowd and addressed the Primarch directly, calling him Lorgar Aurelian and welcoming him to Cadia. This woman, the Chaos priestess Ingethel, would ultimately lead the Primarch down a path of spiritual enlightenment that actually marked the beginning of Lorgar's fall to heresy and Chaos. Later, the Priestess Ingethel of Cadia would initiate a ritual that would see her transformed into the Daemon Prince known as Ingethel the Ascended, and then lead the 1,301st Fleet's scout vessel Orfeo's Lament into the Eye of Terror.

The Serrated Suns Chapter dutifully carried out the final stage of Lorgar's pilgrimage. Entering the Immaterium that made up the hellish realms of the Eye of Terror, the Word Bearers were possessed without their knowledge by Daemons. Unlike later possession of daemonhosts by the malevolent entities of the Empyrean, these initial possessions were less a brutal subjugation of the host's physical body than a symbiotic fusion of both beings on a spiritual level. Indeed, Lorgar would later point to survivors of the journey into the Eye of Terror as examples of what all of Mankind could become if Horus succeeded in overthrowing the rule of the Emperor of Mankind and delivering the galaxy into the service of the Chaos Gods. The remnants of the Serrated Sun Chapter eventually returned to his Legion after a 7-month-long subjective ordeal in the Eye of Terror that lasted for only moments for those of the Legion waiting in realspace for the Serrated Suns' return. During questioning by Lorgar, a Word Bearer by the name of Argel Tal detailed what he had experienced in the Eye of Terror, providing useful insight later used as the foundation for the heretical Book of Lorgar. In honour of his achievements, Lorgar made Argel Tal the Captain of his Gal Vorbak (the "Blessed Sons" in Colchisian) an elite cadre of Astartes made up of the surviving members of the Serrated Sun Chapter. These were the first known Possessed Chaos Space Marines.

Possessed Characteristics
Possessed are easily identified by their grotesque features and mutated forms. They may have vestigial horns, outlandishly warped limbs, membraneous wings, extra mouths and eyes, or enormous talons that can gouge through ceramite and steel. They are superb trackers and can even guide the rest of the Chaos Space Marine through the shifting tides of the Warp. However, their primary role, and that which they relish, is tearing those who deny the superiority of Chaos limb from limb.