From the back cover of the DAW first edition: "I stared up at two tall spires. Between them was a dark area with a crack of utter blackness running down the center, not yet open but plainly threatening. The portion around the crack didn't look like normal sky but was wrinkled and bumpy as if something was striking it in an attempt to get through to my side. Being there looking at the darkness had a strange effect on my mind. I felt as if something sinister was reaching out of the crack to prowl inside my head. It wasn't a piece of ordinary sky stretched up there between the mountain peaks but a fabric of space that threatened to tear open. Something behind it tried to get in, and though it hadn't succeeded, it had forced a small bit of black light into my world."
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