The Datrali are about to attack Avol - the planet of cute, colorful ponies. They are being led there by an evil Unicorn Stallion named Xander.
They are about to find out that the world is protected...
This is a short, amusing one-shot based on "Into the Black: A Mare's Tale" by Shirotora, originally proposed as an 'April Fool's' Chapter a long time ago. Reading the story is required to understand what is going on in my little short here.
And yes, the crossover hints are intentional...