Big Macintosh must thwart an evil pony's scheme to cause a major crop disaster.

The song from the fic "The Great Bale Out" by Fairy-Slayer! fairy-slayer.deviantar...

It is, naturally, a cover of the Perry the Platypus/Agent P theme from "Phineas and Ferb" with Pony-themed lyrics.

Music by me: tinyurl.com/whosthisjerk
Lyrics by Fairy-Slayer: fairy-slayer.deviantar...