While on a trip to Canterlot to do some research, Twilight happens upon a dust-covered book titled Insane Edicts: A Legal History of Equestria. Sure, the book seem innocuous enough, but when she opens it up she discovers that Celestia is far more eccentric than she'd like to believe.

A secret unknown to any hornless pony, unicorn horns are made of candy. Pinkie Pie found out, and now she wants to try every flavor!

Warning: contains awkward moments and far too much non-consensual horn licking. Proceed at the risk of your horn and your dignity.

Available in Chinese, courtesy of Hell Organist.
Available in Russian, courtesy of boatOV.
Audio Reading by CaptainBron3y.
Second Audio Reading by Kanjigirl.
Featured on Equestria Daily.

Based on this story:
Pegasus Wings Are Made Of Ice Cream
The Taste Of Madness
Lyra's Candy Shoppe
Candy Is Made Of Unicorn Horns
How Many Licks?
To Prevent Horn Decay
Unicorn Horns Are Made of Heroin
Over His Dead Body
A Luscious Loophole
Dr. Doofenshirtz's Sweet Revenge
That Thing We Do
#DealWithIt
Unicorn Horns are...
Unicorn Horns Are Loaded With Calories
Charlie The Unicorn's Horn Is Made Of Candy