The earth ponies are fed up with the oppressive nature of the upper class, which consists of unicorns, pegasi, and the Royal Family. They lead a rebellion, with a pony named Joseph Stallion leading them. After defeating the Royal Family, Stallion forms the Poniet Union (Union of Poniet Socialist Republics, or UPSR) and begins to reform society into an equal place for all. The Union then declares war on the capitalist dragons. The mane six proceed to encounter all sorts of shenanigans.

Mild punning is present