Warhammer 40K: What’s A Machine Spirit Anyways

The term Machine Spirit gets tossed around like it’s a catch-all for technology in Warhammer 40,000. But what are they?
A machine spirit is what the Imperium refers to as the inner workings and automated systems within their technology. These are distinct from forbidden Abominable Intelligence, as they lack the ability to enhance themselves. he maintenance and functioning of Machine Spirits in all Imperial technology is overseen by the Tech-Priests of the Adeptus Mechanicus.
Machine Spirits Alive?
The advanced system consists of a combination of organic and mechanical components within the vehicle and in essence act as automated systems. Not all vehicles are equipped with such systems, but vehicles that are can operate entirely on their own without a crew, with some success. The Adeptus Mechanicus believes that Machine Spirits can be influenced by religious rituals and are near-bestial in nature, capable of exhibiting emotions such as hatred and stubbornness.
In particular, the machine spirits of Titans and Knights are revered for their intensity and require elaborate awakening and taming rituals. With devices such as the Throne Mechanicum, pilots of these engines can link with a Machine Spirit directly.
The addition of a machine spirit is advantageous in the case of the vehicle’s crew being killed or incapacitated, as the auto-systems are able to take control of the vehicle, firing its weapons and driving (providing the systems themselves are still functional). However, the machine spirit normally cannot fully replace the abilities of trained human pilots (going that far might trespass on the Imperium‘s condemnation of Abominable Intelligences, and could garner the attention of the Inquisition).
Drop Pods actually possess some of the more advanced Machine Spirits in the Space Marine Arsenal.
Machine Spirits are capable of being corrupted by Chaos, transforming its technology into something that is impure and heretical to the Imperium. The Adeptus Mechanicus also believes that Xenos technology lacks proper Machine Spirits and are thus abhorrent.
The Lord Discordant actually has a corrupted Machine Spirit on it’s model taken from a Land Raider.
Machine Spirits Gone Independent
Even though machine spirits should not be capable of fully autonomous behavior, it has been documented that machine spirits of a certain age are, in fact, capable of exactly that. The most famous example are the ancient Itinerant Kastelan Robots which operate independently until arriving on battlefields, where they allow Tech-Priests to control them, but sever this control once the battle is over.
Land Raider machine spirits are also known of being able to fight without human intervention. For instance, the Land Raider known as Rynn’s Might that belonged to the Crimson Fists Chapter was able to fight Orks even though it had no crew on board, waging a solo war against the Xenos, killing one of their Warbosses and many of his followers overnight, before finally being destroyed.
The Land Raiders actually have document locations of their Machine Spirits thanks to this cutaway artwork. It’s the labeled as the #2 spot.
Finally, the Lightning fighter plane Indomitable Spirit was known to have developed a stubborn and aggressive character during its very long career, aiding its Imperial pilots in numerous ways in combat. When it was captured by the Chaos-aligned Blood Pact, the Indomitable Spirit even seized full control, crashing itself to prevent its new Chaos pilot from shooting down an Imperial aircraft.
We don’t know how they work but we know Machine Spirits are more than the sum of their parts.
For More About Machine Spirits Check out the Lexicanum!
