Board Thread:Warhammer 40k General Discussion/@comment-6078851-20130130174042/@comment-3258762-20130317152807

AdMech = Short for Adeptus Mechanicus

And I see that it says they are from the Emperor, but what I wonder is: Is it from the fluff written by Mat Ward? Because I do not trust the word of the man who said that all other Chapters liked Roboute Guilliman more than their own Primarch and are very sad "for they know they can never be Ultramarines"

Now, if that info comes from someone more trustworthy, then I can accept that they come from the Emperor, but not before that.

As for the Custodes, there is one thing we cannot forget.

The Emperor started working on the Primarchs after he had conquered Luna, and he made the first gene-seed there from the leavings after the Primarchs abduction, but the Custodes (and Thunder Warriors) came long before that. And, as you can read in the Outcast Dead, the Thunder Warriors were not made with any form of gene-seed, which would then mean that neither did the Custodes.