Rainbow Dash is doing what Rainbow Dash does best, second to flying and third to pranking, and that happens to be taking a nap. Unfortunately, her old bragging line, "I could do a Sonic Rainboom in my sleep!" turns out to be true when Rainbow Dash, lo behold, does a Sonic Rainboom in her sleep.
Oh, and she somehow splits into fragments of herself. That's probably important.
Read the next in the series!
Red!
Orange!
Yellow!
Green!
Blue!
Indigo!
Violet!
Black!
White!
Rainbow!