Board Thread:Warhammer 40k General Discussion/@comment-11474177-20130811033139/@comment-6078851-20130811155929

if emps never existed?...

humans would have colonised the galaxy, as they did, but from the age of strife onwards it would all be downhill. no emps - no thunder warriors and no unification wars, meaning earth would remain in the throes of global civil war, (i'm not actually sure how bad the waring was before the u-wars) and there would be no reunification of the separated colonies under the imperial truth. mars would be the next bet for some sort of empire building, and they'd maybe get a half decent effort going but....

without emps there were no thunder warriors, and so no primarchs and no space marines. even if there was a galactic reunification, and the mars empire had access to vast numbers of imperial guard, without the supersoldiers it would always be a losing battle: the bog-standard human race simply would not be able to stand up to the myriad forces of the galaxy (not to mention the uncontrollable chaotic corruption that would be rife). without emps, by 40k the human race would, at best, be individual planets or sectors being inexorably steamrolled or, at worst, would be exctinct.

as for the tyranids, they were heading to the milky way since before humans achieved sentience, and while the astronomican may be a bright and shiny lure for them, they were coming regardless.