You never specified what stone, Possibly me!

"Uhm... Princess?" Raven tapped Celestia on the shoulder. "I believe you should look up for a moment."

Celestia rolled her eyes, setting down her copy of 'Ooga Booga Hot Mares & Stallions, a Pony Plot Publication Presented by Post, weekly!'.

Yes, that there is three different punctuation marks right next to each other.

The Princess of the Sun finally looked up.

"LOOK AT ME, CELLY!" Nightmare Moon's voice reverberated through the air. "I TURNED MYSELF INTO THE YOUR SISTER! I'M NIGHTMARE MOON!"

And that was the funniest sht Celestia had seen.

Nightmare Moon proceeded to be further banished into a black hole for dead memes. Princess Luna was spotted shortly after drifting aimlessly through space now that the moon was gone.