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(By Google Translate:)
 
The plot takes place at the end of the fifth season. Rose attends Twilight’s lecture on cutie marks and the origins of the six girlfriends. There she notices Starlight, senses in her “her” as a former villainess and decides to follow up, as if she did not do what. Meanwhile, in a parallel world, Derpy and Mundrive are assembling a portal to Equestria. During the transition between the worlds, they are thrown in different directions, and the batponyasha literally falls on Rose’s head. Mundrive joins the unicorn mission with interest. So they together get to the place of the intertemporal battle of Twilight and Starlight. Seeing that Twi cannot be defeated, they decide to intervene and destroy Starswirl’s spell - which leads to an unforeseen result. Time streams get confused, and all bad branches of probability come true at once. Two ponies find themselves in a world captured by villains. In the absence of a common enemy, Equestria, everyone lives there in relative peace and tranquility - but our heroines are not happy with this. They want to go back and fix what happened. To this end, Mooney and Rose begin to explore a new dark world in search of a door home. And possible allies.