The Forgotten Equestria

A new species of pony has arrived in Equestria. A species that was long thought to be extinct. A Mesohippus filly named Calypso has showed himself in Ponyville and cannot find his way home. When Twilight's friends find Calypso, they decide to take him to Canterlot to see the Princesses. Celestia is surprised to see Calypso, and has thought his species went extinct during Equstria's Windigo Ice Age after freezing to death. Calypso says that his species had to relocate into an underground cavern leading to a peaceful world to avoid prehistoric predators, and had also vowed to treat each other warmly to avoid freezing to death. Celestia calls the Shell Lodgers to help her get Calypso home, and when they discover the underground world, they learn that it has gone under a Great Depression crisis, and millions of Mesohippus are poor and hungry. Turns out the land has been taxed into poverty by a greedy Mesohippus king named Prince Moneybags after he stole the crown from his brother, and Calypso's father, King Hippus, similar to the events of Robin Hood. The Lodgers and Ponies are unable to stop Moneybags due to his knowledge of black magic and his vast number of guards. Now the Lodge and Ponies must find a way to save the Mesohippus world before they all definitely go extinct.