A Waaagh to end all Waaaghs?
I was just sitting here skimming through my 6th Ed. Big Book and had a thought, yes they are rare but they do happen. If a big enough Waaagh were to head to Terra and drop right down on top of the Emperor's palace and destroy the Emperor would that be the end of Humanity in 40K? I don't think it would even need to be every Ork in the galaxy, just enough to get in and kill him.
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