Was there any time when there was no Blight?
Oh, yes. The Blight is an artifact of the War of the Shadow and the Breaking. There was no Blight before the Bore was created, and the drilling of the Bore did not immediately create the Blight, but the Blight came into being after that.
Was the Blight [mumble] from the Dark One, or one of the Forsaken?
From the Dark One. It is land that has been corrupted by the Dark One.
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