Luna sat deep in the dungeons - former dungeons - below Canterlot. Since her - reappearance?... redemption?... return from exile?... salvation?... purge?... there were so many ways to describe it - she had found solace and happiness in her laboratory. Past the locked doors dwelled the smartest pony you've ever seen. She made Equestria-shattering discoveries and engineered the most amazing inventions.
"Eureka!" She shouted and raised her forelegs in triumph. Her greatest creation was complete. This called for a celebration! She walked over to the fridge and pulled forth a special bottle she'd been saving for this special occasion. She opened it, poured it into a long-stem glass. Raising it up to her lips, she enjoyed the wonderful taste, feeling the bubbles tickle her throat. Ahhh. Nothing satisfied like root beer.
"Oooooooo!!!!! What is this?"
Luna spat out her drink. "P.P.!!! What are you doing here?"
"Just visiting one of my best friends!" smiled Pinkie Pie.
"You know you're not allowed here."
"Aww," whined Pinkie. "Why?"
"Well, let's see... there was the time you blew up my new reactor... the time you created a thousand clones of yourselves... the time you ate my special cookies and grew to be a thousand feet tall... the time you switched my brain with that of a mouse's.... Should I go on?"
"Yes! All those times were super fun!"
"For you maybe. Now P.P., you must leave. I'll show you the way out."
Luna led Pinkie Pie through the lab, past machines of incredible wonder, boiling beakers over Bunsen burners, and devices with buzzing Tesla coils. Luna saw the front door, relieved at no mayhem today. Until....
"Ooo! What does this button do?" asked Pinkie Pie.
"No!" shouted Luna as she lunged towards the pink pony, but it was too late.
Pinkie Pie pushed the large red button moments before being tackled by Luna. Suddenly groans and cracks filled the air.
"No! It's too late!" cried Luna before teleporting herself and Pinkie Pie out of the lab.
Luna and Pinkie Pie stood outside, watching Canterlot slide down the mountain.
"What did I do?" asked Pinkie Pie.
"P.P., you turned off the anti-gravity drive for Canterlot."
"Uh?" asked a confused Pinkie Pie.
"You thought Canterlot was held up by a powerful spell or pegasus magic?"
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