Twilight Sparkle wakes up one morning to a harsh dose of unreality. She is stranded, without her friends, on an island which matches no known locale on Equestria. Surrounded and harried on all sides by the alien and the dangerous, she will find her mettle sorely tested, and find perhaps that the best friends you will ever have in your life are the ones you make when your back is to the wall...

Thanks to CedricBale and noobie56xx for tracking down the name of the artist so I could give them credit.