The noise woke up AK Yearling. She held perfectly still and controlled her breathing, eyes closed, giving every appearance she was asleep. She concentrated on the sounds in her bedroom: the shuffling of hooves, and rustling of feathers. Through her eyelids, she saw the glow of an aura levitating an object.
So. A unicorn and a pegasus. She and Caballeron were friends again, for the first time since an unfortunate expedition near Maretle Beach when AK was still in high school and Caballeron a doctoral candidate, so it wasn't likely to be his henchponies.
But who did that leave? Daring was disappointingly devoid of detractors and disputants of late; Equestria under Empress Twilight's rule was boring.
Hoofsteps scratched the floor close to Daring's bed. She wouldn't get a better chance than this!
"Hyaaa!" AK shouted, opening her eyes and launching out of bed to tackle the nearest of the two ponies. Her Daring Do pajamas flapped in the air. All she could see was the silhouette of the pony in the darkness of her bedroom. She hoped it was the unicorn, so she could hit them on the horn and stun them and then deal with the pegasus.
She landed a crushing blow with her left forehoof against the pony's nose, then an uppercut with the other forehoof under their chin followed by a left cross that connected with their horn. Yes! AK thought. Now to spot the pegasus, and—
"Ow," came an oddly familiar voice, and then royal blue magic surrounded AK and squeezed her like a toothpaste tube, her eyes bugging out and wings smashed flat to her flanks.
The glow of the horn—the horn that had just taken a crushing left-cross—filled the room with a royal blue light.
There was only one pony, and she had wings and a horn.
"P-princess Luna?" AK gasped, struggling for air against the crushing embrace of the alicorn's aura. "Sorry about the nose! And chin! And horn! And butt!"
"You didn't hit my b—"
A booby trap fired, a massive swatter the size of a tennis racket snapping from a hidden receptacle in the ceiling and smacking across Luna's rump with a sound like a thunderclap.
"Eeeeeeee!" Luna pumped her legs up and down, dancing in place, ignoring the smack, and then flicked on the lights, brightening the room. "AK Yearling! I brought so many books for you to autograph!"
Still levitating AK a pony-height above the floor, AK still struggling to breathe against the crushing embrace of her aura, Luna inserted an inked quill between AK's lips and held up a copy of AK's final book, Daring Do and the Double Life: an Autobiography, opened it to the frontispiece, and pressed it against the tip of the quill.
"Sign it 'To Luna,'" she said. "Not 'Princess Luna.' I'm retired."
To Luna, AK signed with the quill, apparently the most immune-to-damage bedroom intruder I've ever assaulted.
Luna's aura snapped away and AK fell to the ground, landing painfully on her butt. The quill fell from her mouth and put a black ink blot on her Daring Do pajamas. "Darn it!" she said, brushing the wet spot and smearing the ink more.
"I'm so pleased to meet you!"
"Why couldn't you meet me at one of my book signings?" AK snapped.
"Princess of the night," Luna said in a sing-songy voice.
"I thought you were retired, 'Luna?'"
"Retired and bored!" Luna threw herself melodramatically onto AK's bed. "My life is ennui and malaise! Tedium and monotony! Bingo games and Sunday brunches! Celestia may enjoy retirement but I'm effectively a thousand years younger than her—well, a thousand and twelve—and I want adventure! Danger! Exploits and escapades!"
"You hurt my butt," AK said, standing up and rubbing her rump where Luna had dropped her on the hardwood floor.
Luna's magic yanked the giant flyswatter, ripping the mechanism from the ceiling with a crash.
"Take me on your next expedition," Luna said. "And I'm sorry about your buttocks."
"I'm retired, too," AK said. "No more expeditions. That's why I go by 'AK' now, my secret is out and I'm done being Daring Do."
Luna hopped off the bed and pointed at AK's pajamas. "Daring Do."
"I get slightly blemished units of my own merch for free."
"Blemished?"
"These pajamas's bottoms didn't have a tail hole, so I had to use scissors to cut the tail hole myself. They're very comfy pajamas."
Luna, in a conspiratorial whisper, said, "I have the exact same pajamas back at home."
AK raised an eyebrow. "We sold exactly one set of extra-extra-extra large in pegasus cut."
Luna gestured on the nose. "Take me on an adventure please! I buy all your merch and bought copies of all your books! In hardcover! You owe me."
"Go home, Luna," AK said. "I don't have anything left to prove. I've raided every temple, necropolis, treasure trove, and ruin in Equestria and all the surrounding lands. I'm tired of risking my life for dusty artifacts."
Luna smirked and levitated up the freshly-signed copy of AK's latest book. Her last book, since she was done with Daring Do and was now writing off-color romance novels under the pseudonym Buck Cringle.
"Oh no," AK said. "Page four hundred and—"
"—and seven," Luna confirmed. She read: "My only regret is that I never found an accessible entrance to the Hall of the Mountain King. This remains the only unexplored ruin from the pre-Harmony era in all of Equestria. I suppose it will be up to the next generation of adventure archeologists to crack this puzzle."
AK shrugged her wings. "What? It's the most heavily booby-trapped ruin in the world. Better adventurers than me have gone in and not come back out."
"I want to go there with you."
AK laughed. "I'm retired. I plan to live to old age, not die at the hooves of some long-dead ancient's traps."
Luna leaned in until her nose touched AK's. "I was born and raised in the Hall of the Mountain King. I grew up there. I know all the secret passages. Including the secret entrances, AK."
AK's eyes went wide. She smiled. "Don't call me AK. Call me Daring Do."
From a distance, it looked like an extinct shield volcano, a long, low massif eroded down from a once-glorious height millions of years before. Low sun shined down on them and a bitter, dry wind blew off the tundra to the north.
Daring studied the mountain through her surveyor's theodolite, writing the numbers down in a notebook. The heavy tripod steadied it against the gusts.
"Daring," Luna said, "I know where the entrance is."
"This is how this works. Methodical. Slow. Careful. Precise."
"You never had 'Daring spent hours tediously measuring the mountain with surveyor's tools' in your novels."
"Because it's boring and readers don't want to read about trigonometry."
"Twilight would," Luna said. "In fact, she would probably find that the best scene in the book."
Daring grunted and scratched out a mistake. Luna was distracting her, and she was a writer, so trigonometry was always a struggle, mathematics her worst subject in school.
Luna whined, "Let's go raid a tomb!"
"Hmmm, the north peak is over two hundred meters above the riverbed..." Daring rubbed her chin. "I suspect that the main chambers—"
"Are under the north peak, yes, yes, I was born there, remember?"
"—are under the north peak. Thank you, spoiler of revelations."
"We called it 'Basalt Buttock'," Luna mused. "Because of the shape."
Daring wrote that down. If this expedition went as well as she hoped, it would probably be worth writing a second last book. It wouldn't be the first time AK Yearling had un-retired. And 'Buck Cringle's' stuff basically wrote itself, so it wouldn't affect 'his' productivity much.
"I'm borrrrrrrred," Luna declared, flopping on her back.
"And I'm concentrating," Daring said, and pulled out her book of trigonometric tables to look up the sine of sixteen point four degrees.
"Zero point two eight two three... uh... four... uh... one six... or so," Luna said.
Daring blinked. "Did you just calculate a sine to one part per million in your head?"
"One part per ten million," Luna said, putting a foreleg over her eyes. "Well, I'm not confident in the last digit. Call in two parts per ten million."
"Well, this survey just got easier," Daring said, putting the book of tables back in her bag.
Luna started snoring.
Daring rolled her eyes and pulled the book back out.
"Here," Luna said, levitating the rocks away from under the overhang. "Here."
Daring's breath caught in her throat as Luna revealed the tunnel entrance that had been hidden for over a thousand years. Her ears trembled and breezies fluttered in her stomach.
"We need to take it slow," Daring said, "we have no idea what booby traps—"
"I know precisely what booby traps there are," Luna said. "I dated Cooked Grenade from high school until he left me for Fluffy Tail," Luna's voice turned to an angry mutter, "that little coltfriend stealer..."
"Oh," Daring said. "Is it possible that changes were made after—"
"Duck," Luna said and strode into the tunnel.
"What do you mean, 'duck'?"
A few seconds after Luna disappeared down the dark tunnel, Daring heard the distinctive schnick sound of a pressure plate being activated. Instincts threw her down to the ground and she tugged her pith helmet tight over her head and closed her eyes.
The explosion roared over her head, heat washing over her wings and back and overpressure pounding at her ears. Once the heat faded, she leaped to her hooves and ran to the cave entrance. Smoke billowed and heat radiated against her face. "Luna! Luna! Oh, oh my word, I killed a princess! Empress Twilight's going to send me to Tartarus..."
Several coughs echoed up the tunnel. "Come on down, Daring! I cleared the traps! And I need your help extracting a buzz-saw from my thoracic cavity and some spears from my rump!"
Daring's right ear twitched.
"Cooked Grenade would have been pleased to find out his traps still worked great after a thousand years."
Daring's left ear twitched.
"Have you any painkillers?"
They strode through a vaulted great hall, carved from the basalt of the extinct volcano. Pillars supported the ceiling, which was lost in the darkness above them. Luna lit her horn for light and Daring wore a firefly-powered headlamp around her pith helmet.
"How deep do the tunnels go, Luna?"
"Quite deep!" she chirped, prancing next to Daring. "At one point, we delved too greedily and too deep and opened a cavern of the underworld. A balrog escaped."
Daring stopped in her tracks, her head going light and fear gripping her guts. Her wings flitted as she prepared to make a hasty escape. She whispered, "There's a balrog loose around here?"
"No, he left some time ago."
"W-what happened?"
"After a three-year war in which we fought him and his minions to a bloody stalemate, Celestia called him to the negotiating table. When Celestia served the first working lunch on the first day of the parley, Larry was horrified to find that ceviche was, in fact, raw fish, and in his fiery rage, he put a rather tasty sear onto it."
"Larry the balrog."
"Somepony once called him 'Barry' and got eaten."
"Naturally," Daring said.
"Anyway, after the ceviche incident, Larry then left of his own free will opened a hibachi grill in an expensive suburb south of Hippogriffia, where the seafood was fresher than here inland."
"Y-you're sure he's gone?"
"Yes, I visited Larry last year. Queen Novo and I had drinks at his establishment. There's an etching on the wall, portraying Celestia in a bib and tucked into the table. She ate an entire grilled kraken in one sitting! I wanted to beat her record, but it appears krakens have been extinct for centuries."
"Krakens?" Daring said.
"Tastes like chicken, but more tentacle-y. Larry's Bar-rog and Grill is the oldest restaurant in the world, and I had luckily made reservations before my hiatus to the moon. That's how long Larry's waiting list is for a table."
"The Crypt of the Mountain King," Daring said.
Luna picked darts out of her wings. "I was not aware—ouch!—that Cooked Grenade—ouch!—was using barbed poisoned darts."
Daring picked a dart from Luna's cutie mark.
"Ouch! And yes, this is the center of the King's domain."
They opened the door and found the tomb ransacked and empty, the crypt smashed.
"Crud," Daring said. "What treasures must have been here?"
"Indeed..." Luna said wistfully. "In the days when this kingdom was young and vibrant, and not a dusty ruin, this place sparkled with gold and gems in the bright sunlight of skylights and mirrors, music and dancing filled these halls as scholars and students discussed philosophy and mathematics and artists made grand masterpieces..."
Daring turned in place, trying to picture it.
Luna blinked away tears. "It was a good place to be a little filly... especially to be an aristocratic filly, daughter of the King's grand vizier and raised with the greatest of privileges and the most brilliant tutors! As the vizier's younger daughter, I didn't have the responsibilities and duties Celestia had, so my life was luxury, play, and leisure."
"I can't imagine," Daring said. She spread her wings and closed her eyes. She turned toward the north wall and felt wind rustle her feathers. "There's a secret passage in that wall. I can feel the air currents leaking around the door."
She and Luna poked and prodded the wall for fifteen minutes before they found the pressure plate that unlocked the door on its hidden hinges.
The long corridor twisted deeper into the mountain. Black basalt closed in on them as the tunnel narrowed and the dankness of a thousand years or more of undisturbed solitude filled the tunnel.
Eventually, the tunnel opened into another large burial chamber. Embossed gold sheets covered the walls with images of the dead pony's life, and the floor sparkled with polished gems set at the corners of lapis lazuli tiles.
Daring looked at one of the gold sheets and recognized a much younger Celestia and Luna.
Luna levitated the mirror-smooth obsidian lid off a large coffin that appeared to be made of chrome, or perhaps nickel.
Daring hopped up onto her rear legs, planted her forehooves on the lip of the coffin, and looked in. The smell was that of dust and age, for the bones were long since devoid of rotting flesh.
Luna, too, looked into the coffin and sucked in a sharp breath.
"Look at this!" Daring said, excitement in her voice. "We've made an amazing discovery! An alicorn, a dead alicorn, and look at the pelvis bone! He's a male! The first male alicorn anywhere in the fossil record!"
Luna levitated up the skull, holding it just in front of her nose, then gripped it in her hooves when her aura spluttered out with a pfbbbtt noise. She stared at the tarnished silver circlet that rested just in front of the dead alicorn's horn. Her ears trembled and she hyperventilated, nose flaring with each desperate breath.
"Luna," Daring said. "What's wrong? You're as white as Celestia."
Luna, her voice weak, gasped, "D-daddy?"
THE END