Sprouting from his face were bushy but tamed sideburns and a glorious bristling moustache that looked as though it would leap off his upper lip at any moment and wrestle the nearest bear.

-Municipal Engines, Night's Favoured Child

"Calling me a monster does not do your vocabulary or my actions any justice."

-Cast-Iron Caryatid, The Immortal Game

"CUTIE MARK CRUSADERS POLITICAL PROTESTERS! SMASH THE STATE!"

-GhostOfHeraclitus, Whom the Princesses Would Destroy...

"We'll talk about that in a second. First, I want you to remember this moment. Just close your eyes and sit here in silence for a little while."

...When I opened my eyes, I saw Celestia was just looking at me with what I might call a pitying expression. "Are you ready?"

"No."

"That's a shame. Now, let me go get your fiancee."

"I'm sorry, my what?"

-whatmustido, Diaries of a Madman

The pipe itself was empty - Nurse Redheart had strongly recommended he give up blowing bubbles for the sake of his health - but it still felt good to have something to grind on when he was in a bad mood.

-Nonagon, Death Note: Equestria

“Bad Twilight Sparkle. No megalomania.”

-Cast-Iron Caryatid, Sharing the Night

"Welcome to the club. We have crumbled cookies and spilt milk."

"Like, why do you have an egg timer? Isn’t that, like, cannibalism or something?"

-Somber, Fallout: Equestria - Project Horizons

“He’s not dead... yet.”
“Whoa. You got plans?”

-Ponky, The Sisters Doo

"You have far more endorphins than I'll ever be able to produce."

-Ponky, Through the Looking Glass and What Pinkie Found There

"Ah— Er, I— Oh, you..."
"And sometimes Y. Language is a fascinating thing, is it not?"

Moowell, A Pony Named 'You'

"We wait for their next charge, then my team pushes back with everything we've got, you hear? We make an opening, then the rest of you follow!"
...
"If you say so. Hey Applejack?"
"Yeah, sugarcube?"
"This is really fun."
"Course it is. That's why we do it so often."

AestheticB, Sparkle's Law

"If we’re going to be monsters, let’s be monsters like Equestria’s never seen. Monsters so great and terrible, the world will never need another monster again."

Nonagon, Death Note: Equestria

"Twi, you had me at secret agent. Then you added fame and glory and space. I think you can count me in."

Forthwith, The Moon's Apprentice

"Come see the Friendship Castle, everypony! It'll eat your damn soul but colt is it pretty!"

ManlyDerp, "If you ain't got anything nice to say..."

Even Power Chord's House of Rock, while a bit misleading, did have a pebble by its entrance which she found intriguing.

Twinkletail, My Sediments Exactly