Narrator:

"When Sombra and Chrysalis joined forces to attack Equestria, Celestia found herself fighting a losing battle. After years of bloodshed, and with the grisly end of the war—and Equestria as ponies knew it—in sight, she took an almighty gamble and unleashed an ancient but deadly spell upon her attackers. And, lo, they retreated almost immediately—but it was already too late, and she had unknowingly poisoned the land with an incurable disease.

A century on, Equestria is a wasteland, a shell of its former self. It is in such a world that one pegasus mare, sheltered from the horrors of the apocalyptic world, awakens. But, when she is forced to flee the sanctuary of her home in order to survive, she finds herself outside and at the mercy of the now-unforgiving land and its vicious inhabitants. Will she be able to make a difference, or will our heroine succumb—"

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Unknown Stallion:

"Woah, woah! Hold up there! You're talking about my Blue, aren't you? 'Cos let me tell you; she's no "heroine". She's a feeble thing, scared of her own shadow half the time, and she's never so much as held a blade as used one. And don't get me started on her personality... She's not selfish, but she's never been the sort to run into harm's way for somepony else. Not without incentive. Nah, she's no heroine. But that's not to say she's not important, and believe you me, if she can get over her patheticness... she could do something great."

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The Pastromorbo Epidemic: an epic tale of survival in a land long left for dead. With worldbuilding galore, more than enough swordfights to keep you on your toes, and plenty of (literally) insane dangers around every corner, you're in for a ride. Can't guarantee you'll make it out alive, though.