One day Princess Celestia and Luna found new technology called “Portal Technology” allowing you to create two portals and enter into one and exit out the other. Using the smartest scientist from all over Equestria, they created a company called Celestial Science, after a few years Celestial Science was THE most popular science company ever, and after a few more years they created a computer called GLaDOS, GLaDOS was a creation of Celestial Science, a personality core designed exactly to be fitted as a central computer mainframe. The project began under the oversight of a stallion named Cave Johnson over the company, and was an attempt to create a fully functional, advanced artificial intelligence which was originally intended to be occupied by Johnson as one of his attempts to cheat death. After it became apparent to Johnson that he may die of moon rock poisoning before development on GLaDOS would be completed, Johnson motioned for the personality core to be based on his daughter Caroline instead.
After a decade's worth of hard work, GLaDOS was officially activated as part of one of the many events during the company's "Bring Your Daughter to Work" day. The scientist started enlisting ponies, pegasai, and unicorns of all kinds as test subjects for Portal Technology, Cave Johnson then enlisted a “special” test subject, a human, and yes, you guessed it, that “special” test subject was me. He enrolled me by using a special portal that was able to jump through universes, he just chose somewhere, reached out and grabbed me. But he didn’t just choose me, he also enlisted six other test subjects with me, to work on my cooperation. Six ponies, there names were, Twilight Sparkle, Rarity, Applejack, Rainbow Dash, Fluttershy, and Pinkie Pie. There a funny bunch, and they were tons of fun to test with, but one day that fun came to a nightmarish halt. One day GLaDOS found out that she was able to take control of half of the facility's features, and she deemed that the scientists were getting in the way of science.
So one day GLaDOS began killing most of its inhabitants by flooding the Enrichment Center with neurotoxin. However, only few if not only one of the staff such as Doug Rattmann had survived her attacks. I, Twilight, Applejack, Rarity, Rainbow Dash, Pinkie Pie, Fluttershy, Celestia, and Luna survived the attack. After the attack Celestia and Luna took it upon themselves to stop GLaDOS, we all wanted to help of course but they said that we needed to stay out of sight incase GLaDOS’s turrets came by, so they both put us in separate rooms that resembled hotel rooms and told us to take a nap there until they returned.