|Initial service date||Unknown|
Only Asphyxious knows the origins of Cankerworm, which may well be the result of his own tinkering amid the mechanisms of countless battlefields. It is certainly true that Cankerworm has followed in the lich lord’s shadow for centuries.
Cankerworm's tail houses a strange device that grafts itself to weapons salvaged from the battlefield. This pincer-like apparatus is well-suited to holding wrecked warjacks in place while its mandibles gnaw at it to separate the chosen component.
Cankerworm attacks with a breed of cunning and sense of self-preservation that makes mockery of life. Skulking across the battlefield, Cankerworm waits for other warjacks to suffer crippling damage and springs to attack the vulnerable machine. As it finishes its target off, it harvests useful machinery from the fallen construct, using its mandibles to tear other warjacks apart before ripping into their exposed mechanical guts. Once it locates a weapon of potency within the wreckage, it flawlessly integrates the weapon into its own systems. This unprecedented ability to manipulate even the most sophisticated and complex mechanikal devices makes Cankerworm a versatile tool in Asphyxious' arsenal.
Even Asphyxious' servants find the bonejack disquieting, particularly as it has on occasion lashed out against those who displease its master. Necrotechs are both fearful and envious of Cankerworm, both apprehensive of and fascinated with the alien intellect it seems to display. None interferes with Cankerworm as it scours the battlefields like a malignant iron insect. Its behaviour is often as inexplicable as it is abhorrent. Cankerworm has been observed to pile the dead after a battle and bury itself in their midst. It has dissected machinery and corpses with equal dispassion and sometimes recovers a skull or a piece of mechanika it considers worthy of its master’s further scrutiny. How it chooses its trophies remains a mystery no one has dared to investigate closely.