Board Thread:Warhammer 40k General Discussion/@comment-5846164-20121209201723

I have read in a spacemarine battle novel that orks are "afraid" the dark due to bad nightvision and they wont even do assaults during night time. now on others this is not even a problem, now who do we say is right? its all published buy black library and so on. so what is like our codex for that? any thoughts? 