ALIENS vs. Predator
Plot: Rainbow Dash discovers Celestia's horrifying past. Celestia and Luna once lived on a different planet and each had a Yautja guardian. There was another race who threatened Celestia and Luna's family. They where called Xenomorphs. In a Yautja village were Celestia and Luna used to live was suddenly attacked by a horde of Xenomorphs. Fearing for there lives the Yautja guardians escorted there children, Celestia and Luna to an escape pod and placed them inside and set the cornets for Equesrtia. They both looked out the window terrified and saw one of there guardians got impaled by a Xenomorph tail. The spaceship then speeded off towards the undiscovered planet. After there landing Celestia and Luna both used there energies to create a new kingdom on the planet which is known today as Ponyville. There population grew from light orbs that came from aftereffects of Luna and Celestia's Light Pulsar. A century later in present time, Rainbow Dash discovers a Xenomorph hive on there own planet. The aliens are now free to wonder around Equestria. Everyone is terrified and have taken shelter in Celestia's castile. She tells everyone about her and her sister's secret. A single Yautja in a spacecraft above the world of Equestria detects a possible Xeno Infestation on the planet below and goes down there to clean up the mess. The ponies are then forced to witness a ancient battle that raged for eons.