It's Hearth's Warming Eve in Las Pegasus, and weather-mare Rainbow Dash has come to see her idols. Instead, she's going to have to save them.

In a skyscraper high above the city, twelve ponies have declared war. Their motives are unknown, and their cause seems to be anything but just. They're as brigade as they are ruthless, and have no reservations against ending a pony's life. The last thing Rainbow wants is to get killed, but she'll have to put herself in the line of fire if she wants to get herself and everypony else out alive.

She's an easy pony to like, and a hard mare to kill.