Thorax has been contacted by Chrysalis with promises of a truce. She doesn't understand how far along he has come in becoming the true ruler of the Hive, but she will.
The changlings have taken over and all hope is long as none is left to stand against them. But in another world there is still one unicorn left. With the help of her old teacher's pet, Sunset must become the hero she always meant to be.
Twilight has been conflicted about being a princess while her friends support it she worries about the responsibility it brings. In honor of her Princess Celetsia makes a new Holiday dedicated to friendship unaware of the danger growing.
When a portal to another world appears outside Canterlot, the ponies' initial reaction is of enthusiasm, hoping to greet these strange aliens with open hooves. Too bad this world was already visited by another Equestria...
Doomguy, Duke Nukem, BJ Blazkowicz, the guy from Marathon, Chexguy, the mage from Heretic, the cleric from Hexen, and Quakeguy all stumble into Equestria. Hijinks ensue.