Board Thread:Warhammer 40k Novels/@comment-27376167-20151210113237/@comment-24091837-20160416081807

Zixis,the fact that the Tau Ethereals have psyker-like power due to pheromone control means it is entirely plausible that a Primarch with his own psyker-esque pheromone control abilities could well have communed with them & thus may be/have been covertly or overtly guiding the Tau through such commication.