Dear Twilight Sparkle:
Ugh. I was having such a wonderful time banished to the sun. Peace and quiet, and no Twilight.
Oh well. If anything, I now have one more thing I can put on my petition to ban the Filly Decimal system. Druggies really have their uses.
And I've noticed that the royal guard kind of sucks. In fairness though, anything that's capable of taking down a full-grown alicorn is probably not going to be fazed by a couple of guards. Of course, this begs the question as to exactly why we even need a guard in the first place.
Oh yeah, that reminds me: you're actually right. Your brother was, and still is, making sweet, sweet love to your foalsitter. Hopefully that should be enough to scar you for life.
Anyway, I was hoping that your quest to find the elements in the deadly forest would lead you to get mauled by a manticore, but I guess that those other ponies had to follow you in. I can't say I blame them, though; nopony in their right mind would want a bitch like you to be the one to retrieve ponykind's last hope for salvation.
But let's make one thing perfectly clear: Unicorns are NOT the master race. That distinction goes to alicorns such as myself. We're basically pony gods, and we rule over the whole world. So next time you go on about how an earth pony sucked at helping you, remember that you'd suck at helping us.
One thing that your letter has made clear, however, is that the drug problem is worse than I had imagined. Between Pinkie Pie laughing at trees, the rest of you being afraid of those trees (Seriously? Trees can't even attack you!), and that weirdo sea serpent, it's like drugs have infested every corner of the world.
Of course, your existence is more than enough to justify cutting spending on drug law enforcement.
And of course, there were the elements themselves. In an ideal world, Nightmare Moon would have killed you before you figured out how they worked. Unfortunately, this isn't an ideal world, and you manged to use five random ponies to make my sister taste the rainbow. I'm glad I got back when I did, otherwise you'd probably try to kill her.
So, there we go. If you hadn't already decided to stay in Ponyville, I'd probably have forced you to leave Canterlot anyway. In any case, I'm not going to miss you. On the other hoof, your constant letters are going to be more than a bit annoying.
Then again, I might be able to have some fun with that...
Your former Teacher, Princess Celestia.
P.S.: I need a new student, so I'm taking your old Smarty Pants Doll.