Board Thread:Warhammer 40k General Discussion/@comment-25222488-20150811023557/@comment-5880884-20150813150732

There are various arguments for whether the Emperor can return or not.

On one hand, it is very possible that the emperor returns since he is a perpetual like Vulcan, Grammaticus etc.

However, He has been absorbing the life force of millions of psykers throughout the ages. That is in addition to the incredible amount of power granted to him through the faith of humanity, and there have been several canon sources which state that Astropaths and even non psychics can see the departed souls of humans gather around the Astronomican (His will). Also, he has the power to resurrect dead faithful servants, grant them incredible power, stop time and even create a warp storm (speculation; Storm of Emperor's Wrath). All these sound exactly like what the Chaos Gods do, and thus sugest that the Emperor cannot be part of the material dimension anymore since he is basically a God now, equal in power to the Gods of Chaos.

So yeah, him truly passing into the immaterium as a God is more likely. It is unlikely that he will come forth as a human anymore.