User blog comment:Squeaky the first/Warhammer and Warhammer 40K, relations./@comment-1932673-20111209154310/@comment-1257337-20111209221408

Yes but think, the warp exists in both universes and is accessed similarly. The only difference is that warp energy actually blows across the old world and thus the warp is not needed to use magic. Take mage and put him on Terra and he'd be powerless against a psyker. I'm sure there is a few 'true' psykers though.