Board Thread:Warhammer 40k General Discussion/@comment-96.237.238.119-20131218020230/@comment-24944355-20170227102127

The Chaos gods are only empowered by a PART of the warp - Khorne by bloodshed, Slaanesh by Lusts etc - the Emperor has the souls of untold trillions of humans who would give him their entire power output not just a part. Also the Chaos gods are wasteful by their very nature while the Emperor is anything but & would get more out his resources than they do. On top of that  the Chaos gods fight among themselves constantly & only unite grudgingly for short periods which reduces their effectiveness even more. The Chaos gods call the Emperor the Anathema - a living bane to their very existence - for a reason & he is quite possibly the only being in the universe, or the warp, that they actually fear.