Kyriss the Perverse was a Keeper of Secrets. Along with Ka'Bandha, he was one of the two daemonic]] "generals" who orchestrated the Battle of Signus-Prime against the Blood-Angels and their Primarch, Sanguinius. Horus and Ka'Bandha however intended to use Kyriss as a "sacrifice" to drive Sanguinius into a rage and eventually turn him to Khorne. After Ka'Bandha was forced back into the Warp, Kyriss informed Sanguinius that he would spare the Blood Angels of the Red-Thirst and Black-Rage if he took the hate of one of his lost sons into him and stepped into the realm of Chaos, but to save his gene-father the Apothecary Meros did instead. In a rage over the fate of his son, Sanguinius decapitated Kyriss.