Laconic / My Little Pony: Friendship Is Magic S3 E13 "Magical Mystery Cure"

Amid a mix-up of cutie marks, Twilight Sparkle fulfills her destiny.
... and it's what the unabridged version's telling me!

http://tvtropes.org/pmwiki/pmwiki.php/Laconic/MyLittlePonyFriendshipIsMagicS3E13MagicalMysteryCure