sorry, pressed enter by accident - what I was going to say was *ahem*
When were the Cadian Pylons built? The implication is that they were built by the Necrons, bu-ut - the Necrons existed way, way back, sightly after the dawn of the univere, and then went into a nice long nap right up until about M39 or so. All well and good - however
The Pylons are apparently there to hold back the Eye of Terror.... however, the Eye of Terror came into being around about M30, the same time as the fall of the Eldar and the dissipation of the warp storms around Earth.... 9 Millenia before the Necrons began to come out of hibernation
So the question is - did the Necrons / C'tan wake up early, and build the Pylons on Cadia - or did they build lots more, way back when, in the hopes of stopping any warp outbreaks - or am I completely wrong altogether?