When Discord first escapes his stone prison, he makes the disgustingly logical decision that Twilight is simply too intelligent to be messed with for long. So, naturally, he picks on Fluttershy instead.

This is Derpy Hooves, eccentric Pegasus, wall-eyed filly, and self-proclaimed 'Welcomer Pony.' Ponies have been found, victims selected, and Derpy Hooves is now on the prowl for the 'fresh-meat,' as it were. Too bad she gave up.