Servo-skull - Notable Variants: Guardian-skull (also Gun-skull or Combat-skull) - Designed with a somewhat reinforced structure and fitted with a single, efficient weapon system and targeting selection programs, Guardian-skulls -- also known as Gun-skulls and Combat-skulls depending on their armament, whether it be ranged or melee -- are uncommon but prestigious and effective bodyguard devices. On Necromunda, a Gun-skull is usually equipped with a compact autopistol and will target whatever or whoever the owner does when they make a ranged attack. Their small size, tireless vigilance, and ability to hover in the shadows silently make them surprisingly discreet and effective servants.Servo-hunter - A variant Servo-skull often utilised by planetary Enforcer cadres and less well-funded enforcement agencies which do not have access to the meticulously-engineered Cyber-mastiffs or Grapplehawks of the Adeptus Arbites. These agents make use of shoddily constructed cyber-familiars to carry out similar duties. Servo-hunters are classic examples of such second-rate technology: these small, comparatively simplistic familiars are an inferior local variant of a Servo-skull, tasked with the exploration of a fixed location and the identification of any potential targets within. Popular amongst the Enforcers of the worlds of the Malfi Sub-sector, Servo-hunters are traditionally encased within the skulls of faithful hunting hounds, as the deceased animal's spirit is said to ensure that the drone's rudimentary logic-engine remains loyal and fierce. A Servo-hunter, when activated and released, will float silently on tiny lift-motor gravitic suspensors and begin to search a nominated area for any targets which match preset parameters (usually human-sized heat sources). When these are located, it will provide its handler with some audible alarm, and will remain alongside the target, sounding that alarm, until deactivated. The Servo-hunter can also be used to patrol an area for intruders, or simply alert the controller if anyone approaches.Harrier-skull - Mockingly known as "Grapple-mice" by the underhive gangers of Scintilla, Landunder, and several other Calixis Sector Hive Worlds, Harrier-Skulls are slowly spreading across the sector. The modified Servo-skulls actually have nothing to do with mice, but earned the nickname because of their unique purpose -- serving as Grapple-hawk decoys. Certain reclaimators can spend a great deal of Thrones to learn how to re-program a salvaged Servo-skull's primitive cogitator-engine with a very specific series of evasion patterns. Something about the evasion patterns triggers a Grapple-hawk's threat/targeting routines, sending the Servitors diving after the nimble Harrier-Skulls instead of their actual targets. As their popularity grows, increasingly frustrated Arbitrators make a point of targeting any Harrier-Skulls first during a suppression raid.Monotask-skull - The most common form of Servo-skull encountered, Monotask-skulls are designed and equipped to offer assistance with a particular task, and most are fitted with a basic set of extendable manipulator pincers and whatever else by way of gear their duty requires.Lingua-Vox Servitor - Useful to diplomats and explorers, a Lingua-Vox Servitor is a specially designed Servo-skull equipped with an advanced linguistic cogitation engine. The Lingua-Vox hovers just over the shoulder of its master, aiding him in translating and understanding unfamiliar tongues.Sensor-skull - A Sensor-skull essentially combines a Servo-skull with a bioscanner and an auspex that allows its owner to detect incoming targets beyond their line of sight.Medi-skull - A Medi-skull is a Servo-skull that has been outfitted with a Medi-kit and the ability to dispense basic first aid and combat stimms from it to its owner.Corpus Mymir - The Corpus Mymir was a type of psychically-empowered Servo-skull employed by Loyalist Mechanicum and Dark Mechanicum forces during the later years of the Horus Heresy. One among many of the innovations of Zhao-Arkhad that saw that Forge World's censure by the orthodox Mechanicum authorities of Mars, the Corpus Mymir was a psychoactive Servo-skull. Contained within the drone, the brain of a psyker was kept at a basic level of activity through a combination of drugs and electro-charge implants, allowing it to maintain some basic telepathic and divinatory functions. Before the removal and implantation of the brain, the donor, who was often forcibly selected from the highly psychically active population of the moons of Zhao-Arkhad, received extensive mimetic conditioning and hypno-therapy, fixating it upon a simple auto-suggestive phrase. Repetition of this phrase by an authorised operator triggered the subconscious manifestation of simple psychic phenomena by the Servo-skull. The fact that these devices, often prone to catastrophic failure, became commonplace on the battlefields of the southern Imperium during the savage inter-Forge wars of the late Horus Heresy speaks as much of the desperation of the combatants as it does to the efficacy of the weapon.