Sh'a has been made by or is controled by Dreadlords?

[Slaughty8]

I think that this would fit, as I don't see any reason why they couldn't just lay some kind of magic to experiment on Pandaria in case of their Burning Legion's Crusade failure or something. Makes sense. It is a wild guess but may fit.

Garrosh could be simply possesed by daemons magic, just like his father. He gravitated to Sha almost from the begining.

All this could be a great opening and initiation to possible next Burning Legion (well, most of us expect this expansion).

[Therougetitan]

This is the origin of the Sha, no demons involved

http://www.wowpedia.org/Y%27Shaarj

[Divinism]

Well I think it has been confirmed that the sha are of old god origins; they're seemingly remains of the seven heads of Y'Shaarj.

[bohapjut]

They're born from an Old God's body

[Slaughty8]

Oh, well, my bad. Thanks for pointing this out.