An outside world of anthroprmorphic animals finds a way to deep space travel. Finding a wold that they may wish to trade with. The Alliance sends It's survivor. A List line class ranger. (Kind of puts you in mind of karmen rider.)

This story takes place far in the future of Equestria. The main six have all went Alicorn now. And Luna And Celestia are about ready to hand the kingdom over to the six. When this strange visitor comes from the old mirror (From Equestria Girl)