Sapling, a filly from Stable 12, was raised as a Gladiator of sorts but managed to escape that life. When she is forced to return to the Arena, she destroys it and flees. Unfortunately, her actions have set events into motion that can't be undone. Now she and her companions must face the consequences of her actions as they travel through Derby, a section of the Wasteland on the outskirts of Equestria.