We dont know the nature of the Rangdan Xenos yet. But is that farfetched to believe theyve been able to corrupt or psychically dominate the armies sent their way? Just look at the Enslavers and the Storm Wardens, forced by the inquisition to inter their infected brethren and erase all records of them.
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Imagine a primarch, or even two with their legions, succumbed to alien domination and made to fight their brother legions. Now that would be something the Imperium would want to scour all records of, as it would be extremely damaging to morale and the fledgling imperium. Especially so if the dominated legions had managed to cause terrfic damage before they were bought to heel.
And the blurb states it took the intervention of the Emperor himself to end the Rangdan threat.
Though. The Labyrinth of Night? We have the Noctis Labyrinth on Mars. Could the Rangdan possibly have been an early and quite LARGE Necron dynasty? Some necrons has been said to be awake during the Great Crusade and the Silent King claimed to have met Sanguinius. And the Necrons have mind shackle scarabs that works even on Astartes as seen in Damnos.
Last edited by Brother Lucian; 03-05-17 at 06:29 PM.