Trapped in Equestria together, a brony and an anti-brony come to terms with their new life. At the same time, a new power threatens to unmake all of Equestria.
You are...you can't remember, so lets just go with Anon. You are Anon, and you have arrived upon Equestria as the result of a magical spell cast by Twilight Sparkle...your new roomate.
Tanith First and Only Cross-Over. Equestria joined the Imperium of Man, and due to Imperial Law homeland of ponies need to provide Imperial Guard Regiment of their own. Colonel-Commissar Ibram Gaunt is sent to ensure everything is going well.
When Twilight Sparkle went to bed, she had friends she loved and a life she enjoyed. But she awoke to hospital gowns and padded restraints. And the doctors, they keep telling her that she is sick and none of it was real. They’re lying, right?