In the year 1935 E.C., the continent of Europa is dominated by two superpowers: The autocratic East Europan Imperial Alliance in the east and a commonwealth of loosely allied democracies known as the Atlantic Federation in the west. The economies of both powers depend on a precious multipurpose mineral called Ragnite. Its growing scarcity results in the Empire declaring war on the Federation, sparking the Second Europan War.

The Empire began locking children, from kids to teens, in concentration camps to try and break their wills and make them join The Empire as slaves. Only for one of the children to gather many of them and performing a coup on the camp's leader, freeing many children and stealing many weapons, while the Federation didn't do anything but focus fighting the Empire.

These children made the Underdogs, a freelance group of kids and teens that fight the Empire to free others like them. After a successful raid, a concentration camp the group is suddenly teleported to Equestria by an unknown entity to aid in a war against a rival continent called Fœnum. All because some snobby nobles couldn't keep their mouths shut during an important gathering that was supposed to bring peace.