Sanctus

The Sanctus is a Genestealer Cult's chosen killer, a hybrid bred and honed to remove any obstacle to the brood's survival and spread. When the Patriarch marks a target for death, it suffuses its Sanctus with a trace of that victim's psychic spoor, a telepathic scent the assassin follows like a bloodhound through crowded spire-tops and winding sublevels alike. No matter how deep its prey goes to ground, the Sanctus will find them.

Everything about the creature is shaped for murder. Its limbs are multi-jointed and its musculature malleable, letting it fold itself through the narrowest apertures and squeeze into spaces no ordinary killer could reach, and it moves in perfect silence, slipping past sentries as though they were not there. Unlike almost every other bioform of the cult, the Sanctus is a solitary thing, rarely mingling with its broodkin, a lone predator that keeps its own cold counsel.

In its role as sniper it wields a bio-dart that strikes with uncanny precision, and at close quarters a soulsight blade that it turns upon enemy psykers with particular relish. Whether from the shadows at range or with a whisper of steel in the dark, the Sanctus exists to end the lives that endanger the cult, and it pursues that purpose with a patience and certainty that few marked victims ever escape.