User blog comment:Khalael/Updated Necron Fluff/@comment-1257337-20111027222633/@comment-10514705-20111028143642

I don't actually know all of the details of the fluff as (unlike with the models) their is little physical evidence, as all of this is from the mouth of a GW sales guy, and has been (and now I use the term very loosely) "verified" by a lot of the internet rumours which seem to concur with what he said.

Now, as for the C'tan, from my understanding the Necrons agreed to a pact made by the deciever, one which meant that they gave up their organic bodies. They then, with the help of the C'tan, eliminated the Old Ones. However, after this, they turned against the C'tan, who had been trying to become the masters of the Necron race, and began shattering them into Shards (which they can control). However, these Shards can never be destroyed, only broken further. Does that help clarify anything?

Oh, and it seems the Tom... I mean Necrons wish to find the perfect race to transfer their consciousnesses into, so that they once more have a biological form. Okay that's all I know. Go check Dakka Dakka for more rumours if you like.