LogFAQs > #980018128

Guide posted...

Close, but no. Astartes are normal(ish) humans that, if successful in becoming candidates, get mass produced organ n' stuff shoved into them to become Astartes proper. These organs are the ak47 of augmentation: Generic, not perfect, but easy to mass produce and fairly reliable. All this stuff is heavily modified organ clones of clones of clones of Big Daddy E himself. There's the geneseed organ that is harvested from dead marines, which contains the genetic information necessary to keep production steady and stable. Chapters get fucked pretty hard if they lose a lot of geneseed, like losing your password and needing to reformat your drive just to have a drive to work with again.

Custodes were custom-crafted, chosen at first from Thunder Warriors (long story) and then from the infants of good bloodlines. They don't get that prepackaged organ junk. They are heavily modified down to the cell from birth, using rarefied superscience, and (only presumably) dna from Emps himself. They are individualistic, have custom abilities and gear, and serve the Emperor directly. The Astartes do their damnedest to fit in with each other all time and are constantly on the battlefield, taking orders from a chain of command.

Sheesh I meant this to be short. tl;dr Astartes are generic army jeeps, Custodes are souped up, overtuned supercars.

what does this all even mean lol