Where the loyal Knight Houses' Sacristans are trained by the Adeptus Mechanicus, Idolators learn their craft within the Dark Mechanicum's screaming soul forges. There they learn to conduct diabolic rituals, that enable them to glean the knowledge of how Chaos Knights function and how to desecrate Throne Mechanicums, in order to corrupt Knight suits. These Idolators will then work together in groups known as cabals and there will often be many of them on any given Fallen Knight World. Each will have the ability to repair battle damage on Chaos Knights, but some will have learned additional rituals that will greatly aid their Household or noble they serve.
Some can increase a Chaos Knight suit's power level, while others can subjugate their master's enemies, through psychic yokes and spiritual shackles. Then there are those Idolators who have learnt the sorcerous ways of the Warp and can provide glimpses of the future, so that the ruler of a Traitor Knight House, can better direct their next campaign of terror. Thus a cabal's strength within a House, can rise or fall depending on the services they can provide their masters. This leads to competitions between different cabals, which is encouraged by the Traitor Knight Houses, and it is common for Idolators to wage war on each other. However should a cabal fall out of favor with the House or Nobles they serve, the Idolators can be killed by their former masters. Such actions are not taken lightly, though, for to incur the ire of the Idolators is to invite a nightmarish demise. Many a Traitor Knight Noble who has slaughtered an Idolator, has subsequently been devoured by their own Chaos Knight suit, or has had their soul ripped to screaming pieces by a Warp-surge within their Throne Mechanicum. That is why the more cunning nobles ensure that the surviving Idolators, have some other target for their wrath to fall upon.
- 1: Codex: Chaos Knights (8th Edition), pg. 39 - Corrupted Knights: Idolators
- 2: Codex: Chaos Knights (9th Edition), pg. 17