"I shine brightest in the dark. I am there but cannot be seen. To have me costs you nothing. To be without me costs you everything"
The world ended, a plague turning unicorn and alicorn alike into bloodthirsty monsters.
In its aftermath, with her lands and ponies still recovering, Princess Luna leads a team to the isolated village of Somnambula, the last part of Equestria left unaccounted for.
There are doubts that anypony survived in the month-long heat. But among the ruins of a civilization older even than her own, the Princess holds out hope.
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This is a side story to BaeroRemedy's excellent story And Hell Followed, which I absolutely recommend reading before this.
A big thanks to BaeroRemedy for going over the story.