Servo-skull

In all their grimey fashion

A servo-skull is a kind of machine used by the Imperium of Man. They are made from the skull of a deceased Imperial servant with a cogitator, some sensoria, and a hover-drive installed to make it move. What better way to reward an adept of the Administratum for his decades of shuffling around papers that nobody ever reads again than to make his skull into a little flying robot?

Uses

Much like the drones used by the Tau Empire, the Imperium puts servo-skulls to many purposes. Some of them are used as pict-recorders and message couriers, others as remote viewers linked to a controlling tech-priest, still others as psychic foci or targeting computers to assist Inquisitors and their retinues. Occasionally they have pistol sized weapons and can be used as assassination tools or a hands-free ranged weapon.

On the 40k tabletop, if you field Grey Knights they are often considered a prerequisite. They are placed on the battlefield (and can be placed anywhere outside the enemy deployment zone) after deployment areas have been determined, but before any forces are deployed. Enemy infiltrators cannot set up within 12" of a Servo-skull and enemy scouts can't use their pre-game move to approach within 12" of a Servo-skull. A friendly unit arriving by Deep Strike rolls one D6 less for scatter if it aims to arrive within 12" of a Servo-skull and friendly blast templates placed within 12" of a Servo-skull roll one D6 less for scatter. They can't technically be destroyed, but if an enemy gets within 6" of one it will be removed from play.

Whilst in 30k, they behave as familiars and are taken as wargear attached to your characters. Granting them an extension of their senses, which translates into +1 to invulnerable saves due to enhanced reflexes and also allows them to re-roll characteristic tests (like Toughness or Initiative)

Famous Heads

One particularly "renowned" Servo-Skull is that of Brother Brantor who was a marksman in the Deathwatch. Somehow rather than getting the honoured rest that he deserved, his head never left the service of the Ordos Xenos, who then fitted it with a stealth anti-grav and a whole range of sensors and auspexes (presumably because a Space Marine's skull might be big enough to fit everything) which makes it/him extremely useful for recon missions and the like. Improbably, the skull is also a better close combatant with an increased weapon skill, which certainly cannot be a carry over of experience, since all brain matter is replaced with cogitators, so obviously the Ordos Xenos still knows how to get access to high-quality artificial intelligence or warp shenanigans are afoot.

An unusually talkative Servo-Skull is found among the crew of the Caestus Metallican in Warhammer 40,000: Mechanicus. Formerly a Magos Dominus, Servo-Skull Reditus acts considerably more intelligent than others of his kind, providing commentary on various issues faced by the tech-priests. In fact, the game's intro is narrated by Reditus as he waxes lyrical on the joys of being freed from flesh and serving the Omnissiah in death. His primary duty is to act as the POV camera for the turn-based battles against the Necrons, allowing player character Magos Dominus Faustinius to better command his troops. Considering that most other Servo-Skulls are creepy mute robo-drones and not undead tech-priests spouting philosophy he's probably an example of tech-heresy.

Cherubim

"A cyber cherub clattered in a clumsy search pattern around the scriptorium on metal wings. Such things were grotesque, techno-alchemy far removed from the purer machinery of his day. The madness of Mars had infected everything;

The cherub’s emerald eyes flashed at each word. The sensibilities of this age did not appeal to Guilliman. Hateful art for a hateful time;

The primarch watched it go back to its roost with critical eyes. The wings were more than adornment; from the sound of it, there was not enough lift in the gravity impeller to keep it aloft. The machines of this millennium were crude. The engineers among his brothers would probably have caught the thing in a net and rebuilt the motor; he was close to doing so himself. Either that, or tossing it out of an airlock into the void and replacing it with something less ghoulish."

– Big Bobby G, reviewing a Cherub in Dark Imperium

Wild flying babies. Unfortunately trying to put a diaper on one of them is a painful and arduous task.

One particularly messed-up variant of a servo-skull is the cherub (plural: cherubim), which uses a vat-grown baby instead of a dead servant's skull as the base structure and therefore have much more in common with your garden variety servitors rather than simple robotic machines.

It sounds like something Slaanesh dreamed up, but apparently it's all the rage for higher-ups in the Ecclesiarchy to have little choirs of the things to sing hymns.

One member of the GW staff went to an extraordinary length in describing where they came from and what various purposes they are suited for. According to the history, they first turned up in M33 to celebrate the ascension of the Emperor to the Golden Throne, where the Adeptus Biologicus released 2000 cherubs into the Throne Chamber (one for each year of his enthronement) where they all flew up into the rafters to sing hymns and remain there still, being maintained by the Mechanicum, and presumably shitting on everything just like pigeons do. This act just serves to make The Emperor's torment greater, not just because of the Religious reasons, but because Cherubs are made from Babies.

While singing hymnals is certainly what Cherubim are most well-known for, they do have a number of other roles, since unlike servo-skulls they do have at least some level of intellect to be able to perform complicated tasks.

Goge Vandire had them installed EVERYWHERE during the Age of Apostasy, acting as mobile CCTV cameras so he could spy on everyone looking for sedition.

Some starships have Cherubim aeries installed to help out with menial everyday tasks, though this generally freaks out the common crew as having feral babies flying above your head is pretty poor for morale.

Guilliman is not a fan of them (see above quote). Neither is Magnus the Red.

Types of Cherub

Other less documented roles include:

• Butler - Basically a house menial, attends to cleaning and serving things when expected.
• Crusader - Adorable teddy bear sized servitors in plate, as if being surrounded by armoured babies makes you appear more threatening.
• Custodian - Tattooed with Hexagrammatic Wards, these ones are trusted to carry proscribed artifacts.
• Foci - Psychically attuned to their masters, and can be used as psyber familiars.
• Gregori - Little dudes with freakishly large eyes, fitted with auspex scanners
• Harpy - Babies with blades attached to their feet, are almost always female and are used as combat pests.
• Incensor - Babies carting around fog machines. Sisters of Battle tend to use them to help refocus their faith.
• Love Angel - Cupid in 40k for people who like to be watched by cyborg-children while they do it (You wish I was kidding). They exude pheromones to heighten sexual attraction. How the fuck this has not gotten purged as Slaaneshi heresy is unknown.
• Reaper - Babies dressed in dark robes, come equipped with digi-weapons to remove people bothering their masters.
• Shining - these have refractor fields built into somewhere in their bodies. Not really useful to its master unless you send it somewhere for a different reason where it's likely to be destroyed.
• Squire - Babies with muscle augmentations, which can hilariously make them stronger than full grown adult humans. Their purpose is to hold whatever gets passed to them by their master.
• Stenographer - a much more discrete quill servitor, records everything said in its location.
• Swift - Much larger wings which allows them to generate more thrust and speed.
• Sycophant - Carries around a mirror to let you know how special you are.
• Tailor - fixes clothing handed to them using an onboard supply of thread.
• Weapons Loader - exactly what it says, tiny people trained to reload a weapon when it's given to them. Space Marine Devastator Squads in particular use these quite frequently (named as Armourium Cherub).

While some Cherubs can be manufactured to perform multiple roles, there is always a limit to how much a single servitor can be expected to carry out. Hence, you might find a pack of cherubs built as butlers to attend the care of a household, but also double up as harpies to chase off unwelcome guests.

Thus there is actually a second list of more complicated tasks that Cherubim might also be created to perform usually to the exclusion of anything else:

• Chorister - The typical singing Cherub that is well known across the Imperium. Probably more complicated because they need to know an extensive back-catalogue of songs to sing. Some also know how to play instruments and carry around incense burners.
• Generator - Essentially a flying force-field. These ones have massive, clunky power field generators built into their bodies.
• Grenadier - Dressed up like little soldiers, these ones carry bombs and set them up wherever ordered to by their masters.
• Healer - A medic, equipped with a variety of medicinal tools. Unlike a medical servo-skull, which are tools for 40k doctors and carry their kit where directed, these little critters can actually attend to wounds and simple illnesses on their own without prompting.
• Jailer - Floating interrogation tools, carrying psy-nulling manacles, shock collars and a variety of drugs. Basically your BDSM baby.
• Messenger - much more complex than messenger servo-skulls. Rather than hunting for a person based on likeness alone, they are equipped with pheromone sensors and can track a target by smell and deliver a cogitators worth of information. They are also always built as Swift Cherubs too for quick movement.
• Pariah - They can do it via cloning anyway due to blank souls not having troubles in cloned bodies, making Inquisitorial Agents and Culexus Assassins, so why not have an untouchable baby? Comes with a handy limiter to turn the field on and off.
• Sage - Carries archeotech relics that perform specific effects, because nothing says opulence like having feral flying midgets using your most fragile and expensive equipment for you.
• Seer - Blind cherubs that have somehow been Soul-bound to the Emperor, which must make them hellishly expensive/rare if this is the case. Their purpose though is to channel psychic backwash from perils of the warp from psychic masters.
• Spy - Little Ninja servitors often cloaked in Chameleoline, they have augmented lungs that allow them to resist airborne toxins, a sophisticated on-board suite of short ranged cyber senses for detecting poisons and they also have implanted multi-keys and know how to pick locks.

Nephilim

In quite possibly the most grimdark of grimdarkness, there is actually an upper category of Cherubim, referred to as Nephilim (which means Fallen).

While it is rumoured that rarely a tech-priest can create a master-crafted Cherub with a considerably higher intellect, the truth is that occasionally Cherubs are manufactured using ACTUAL BABIES rather than vat grown ones (perhaps too grimdark for mainstream GW, hence the article was labeled as "unofficial" with heavy emphasis on the inverted commas).

The difference is that vat-grown servitors have no developed central nervous system, which essentially makes them living vegetables until they are given a directive to follow. In the case of human-servitors, they already have a developed CNS and therefore are able to be trusted with multiple complicated tasks and actually use their initiative to figure out what needs doing.

Thankfully, it numbers the times that Nephilim have been made since they are regarded as extremely uncommon; only 22 times since M36 and each for personal reasons determined by the owner and not just for creating a "better" Cherub.

• One Nephilim, "L", was a psyker of such power that it was impossible to transport her via Black Ship, so the Inquisition fixed her into an angelic lightning rod that served the inquisitor for 157 years until it was destroyed by a Daemonhost.
• Another case file was on Maya's World in 076.M41, where a certain Lord Torrington had his comatose son made into a Nephil rather than watch him die. Unfortunately, due to Imperial inheritance law, the Servitor was eventually named Duke and has been the head of the house ever since.