Changes

True cannon conflict emerged with the audio drama [[Oath of Moment]]. In the story, former [[Death Guard]] Captain [[Nathaniel Garro]] travels to [[Calth]] during the [[Word Bearers]] assault on the [[Ultramarines]]. Garro helps defend an access tunnel from the Word Bearers, and at the climax of the assault a machine described almost exactly as a Defiler attacks. The following is a direct word-for-word recount from the audio drama:

"''...and from behind the ridge line emerged a great construct of steel and cables, armor and brass. It clattered across the stone on four jointed piston hissing legs; crab-walking as it crushed the unwary in its path. An angular turret thrust up from the center of the mass, overloaded with guns and fearsome blades protruding in a spine-like formation. It had a main cannon made from black iron with a yawning muzzle dripping with penitent chains. The machine moved like it was alive, its flanks arterial red and dressed in the ebon detailing of the Word Bearers.''" *⁷

Although never called a "Defiler", the machine's description perfectly matches that of a Defiler. It may be that the machine was a proto-type Defiler as the Word Bearers had been worshiping Chaos for longer than the other Legions, and would have more knowledge on how to construct such a machine. This would mean that the first Defilers were from the Word Bearers Legion, not the [[Black Legion]]. This would also mean that Abaddon could not have ordered the creation of Defilers, as they had already been in existence since the Horus Heresy.