[@FacePunch]

Don't forget the Legio Titanicus, heck a couple Baneblades would probably do Prime in with a few volleys, those things have fire power. But God-like meaning a god or someone near that power level? The emperor of man is so powerful he can wipe out legions on his own in a single stroke, entire armies in a handful of strikes, and damn near an entire faction in a few days. But 40k was pulled for other reasons too... Like the Titanicus. The size of the army is so massive that by sheer numbers, they would have won almost automatically. 

We're talking Hundreds of "Pre(never happened) Heresy Custodes, At least a few hundred Thousand Astartes, And TRILLIONS of guardsmen as far as infantry goes.