Board Thread:Warhammer 40k General Discussion/@comment-98.81.158.208-20140213190331/@comment-86.141.22.238-20160113222410

well, there is some early HH book which it mentions that the Emperor betrayed the Chaos gods and Horus suggests that the Emperor went through some kind of similar ordeal in the Chaos realm and came out better for it.

Maybe it way like highlander, the energy of the killed chaos nasties seeped into him and enchanced him or maybe he was granded some powers in a Spawn (the comic) type 'deal with the devil'. Don't know, can't know as yet so I'll speculate like the rest and wait and see what the score is.

I have a feeling it's more to do with a seepage of power than a gift but twists and revalations are abound in the HH series.