Chrysalis and King Sombra work together to take over Equestria, but whilst Chrysalis attacks Celestia, king Sombra steals the Elements of Harmony and locks the mane 6 in a dungeon that can only be unlocked by Sombra's own horn. Celestia's power is drained but before it's completely gone she casts a spell that summons some very unlikely heroes to Equestria.

Twilight can't wait to try out some new spells only alicorns can cast but It all goes a bit wrong when she realizes she missed a page and instead of just affecting her friends the whole of Ponyville has been thrown into chaos. Twilight, her friends and everypony's favourite background characters have to sort out the mess the spell got them into before its too late.