It's based off the 'Fall Out Equestria' Fan Fiction so lets get to it.

Sweetie Belle is one of the survivors of a 'War'. In another world Russian and American scientist have built a portal device. They sent a scout drone and Recon team into the 'New World' and what they find is a Nuclear Wasteland with Destroyed Towns. While in a Helicopter, Artyom a Russian sniper saw a small heat signature by a destroyed train station so he tells the pilot to land by the station. What he found was nothing they had expected.

I do not take credit for the Characters in the Story besides the humans. I got the name Artyom from the book and game known as Metro 2033. Sweetie Belle is Hasbro's Property. The vehicles belong to there creators.