Several days ago...
"Oof! Hey, get your stinkin' hooves off me, ya creep!"
"You want another smack upside your head? Shut up!"
"How about you kiss my flank instead?!"
"I said SHUT UP!" *SMACK!*
A young earth pony with light-yellow fur and a chocolate-colored mane hit the floor of a small, dimly-lit storage room. As she rubbed her head, the cloaked pegasus that struck her gave her a strong kick to her side.
"Maybe next time, you'll learn your lesson," he taunted as she clutched her side in pain. With a chuckle, he left the room and shut the door behind him.
Dusty Runes slowly got to her hooves and lunged towards the closing door. As soon as she reached it, she heard a small click of a lock and started pounding her hooves furiously. "Oh yeah?!" she screamed. "You'd better hope you're not here when Daring comes back and stomps all of you!"
"Ha!" the pegasus laughed loudly. "That's if Night Shade's spy doesn't get to her first!"
Dusty dropped onto all fours as she heard the laughter fade away. Wrapping her light-brown cloak around herself, she closed her eyes and sighed, praying for her friend. "Please stay safe, Daring..."
It had been a few hours since she and Daring Do were ambushed during their train ride to Ponyville and dragged off to... who-knows-where. Daring managed to break free and escape with the Relic of Flight, but not before suffering major injuries at the hooves of Night Shade and her followers. Dusty almost escaped with her, but at the last minute, a gate closed, separating the two of them. Daring furiously tried to find a way to pry it open, but...
"Daring, don't worry about me! Just take the Relic and run!"
"Like hell I am! I'm getting you out of here now!"
"Just leave me, I'm only gonna slow you down!"
"Dammit, Dusty, I'm not leaving you with these psychos!"
"The Relic's more important! I'll be fine, just get that to your friends first!"
"No! Just give me a minute-!"
"THERE THEY ARE!"
As the two argued, several of Night Shade's goons showed up, quickly moving in to capture them. The last thing Dusty saw as she was dragged away was Daring Do furiously pounding on the gate, yelling at the top of her lungs.
"Psst..."
Dusty's ears perked up when she heard a voice whispering to her. She quickly turned around. "Huh? Wh-who's there?" Her eyes wandered for a moment, until she spotted somepony sitting on the floor against the back wall, gesturing to her.
"Who... who are you?" Dusty asked as she approached slowly. Upon closer inspection, she noticed that the pony was an elderly unicorn, with dark gray fur and a light blue mane. On his flank was a cutie mark of a crescent moon.
"Dear... my name is Moon Dusk," the unicorn answered. "A former teacher at Canterlot's School of Gifted Unicorns. And the pony who calls herself Night Shade... is not what she seems."
Present day...
"So this is the place, huh?" Sunset remarked, lifting the brim of her fedora.
"Looks like it," Twilight replied, lowering the map floating in front of her.
Underneath the night sky, Sunset and Twilight were standing at the mouth of a cave hidden on the outskirts of Canterlot. Sunset was geared up in her Mare-Do-Well costume, while Twilight donned a black bodysuit and cloak. The two of them had a difficult time getting the location of the hideout from Night Shade's thug (despite being threatened by two of the most powerful ponies in Equestria, he still insisted on flirting with them), but they finally managed to squeeze it out of him, thanks to Fluttershy's Stare.
Daring Do wanted to go after Dusty Runes, but according to Fluttershy, she still needed more time to recover from the injuries. After seeing how frustrated Daring was, Sunset volunteered to go out and rescue her. Daring was reluctant at first, but she eventually agreed to it.
Twilight and Rarity added a few short-term enhancements to the Mare-Do-Well costume: padding at the bottom of the hoof sleeves to silence her steps, a miniature hoof-mounted crossbow with tranquilizer darts from Zecora, and a small belt with pouches containing smoke and flash bombs. In addition, the costume's color scheme was darkened, allowing Sunset to hide in the shadows more effectively.
Twilight turned to Sunset. "Now remember, those tranquilizer darts are only effective for thirty minutes," she explained. "It can take a while for it to kick in, though. And you've only got a limited amount, so only use them when you need to. Same with those flash and smoke bombs."
"Right," Sunset replied, pulling the mask over her head. "Once I find Dusty, I'll meet you back here, and then you can teleport us back to Ponyville. Until then, try to keep out of sight in case somepony comes by."
"Alright, then," Twilight replied, turning around. "Good luck, Sunset." With that, she quickly galloped off into the nearby forest.
"Thanks, Twilight," Sunset murmured quietly, before turning to the cave. Taking a deep breath, she slowly stepped inside, vanishing into the darkness.
Mare-Do-Well quickly but silently followed the path until she came to a staircase at the end of the tunnel. She crept down the steps, noticing that her hoofsteps were completely muffled by the padding below them. Mare-Do-Well descended the staircase, keeping her eyes and ears alert. Arriving at the bottom, she stepped into a wide, underground courtyard.
Mare-Do-Well dove behind a low wall, keeping her head down as she did a quick survey of the area. She noticed a couple guards patrolling the upper walkways, along with a couple stationed on the ground floor. Crystals lined the walls and pathways, lighting up the room. And at the opposite end stood a gate, which Mare-Do-Well assumed was the entrance. Unfortunately, it was sealed, and two guards were stationed directly in front of it.
Okay, that's out... hopefully there's another way in... She looked up, noticing a series of catwalks above her. I need to get up there for a clearer view of the area... but I can't teleport, I might blow my cover. She quickly looked around, spotting a series of collapsed ruins nearby that looked climbable.
Making sure to stay down, Mare-Do-Well swiftly made her way to the ruins, stopping as she approached the corner. She took a quick peek down the adjacent path, spotting an approaching patrol. Crouching down, she waited for her target to get closer. Once the guard rounded the corner, Mare-Do-Well quickly jumped up and wrapped her forehooves around his mouth, putting him in a chokehold. She held on tightly as he struggled to break free, or at least get his mouth uncovered so he could call for help. After a few moments, her captive's struggling ceased as he fell into unconsciousness.
Lowering his body, Mare-Do-Well quickly checked to make sure he was alive before dragging him out of sight. Hopefully no one noticed... she prayed as she climbed up the ruins and jumped onto the catwalk, doing her best to stay out of sight.
Pulling herself up, she spotted another patrol closing in. Thankfully, the catwalks weren't as lit up as the courtyard below, so Mare-Do-Well managed to stay hidden thanks to the darker costume. Crouching down, she raised the small crossbow attached to her right forearm. Using her other forehoof to steady her aim, she fired a tranquilizer dart at the unsuspecting guard. He stopped in his tracks for a few moments before slumping over and hitting the floor.
Smirking underneath her mask, Mare-Do-Well quickly ran past the sleeping guard, keeping an eye on the courtyard below her and her ears open. From her new vantage point, she could see more of the courtyard, including a previously-hidden passageway above the sealed gate. Bingo.
Keeping out of sight of the other patrols, Mare-Do-Well crept silently across the catwalk. Stopping above the gate, she crouched as low as she could and peered over the edge, spotting two guards marching side by side on the walkway below her. Arming another tranquilizer dart, she waited for them to pass before jumping down, using her cape to slow her descent. Landing quietly, she quickly sneaked up to the guards, firing her crossbow at one. As he hit the floor, the other guard jumped back in surprise, only to be grabbed from behind by Mare-Do-Well and smothered into unconsciousness. The costumed mare stashed their bodies behind a stack of crates nearby, and slowly approached the passageway leading into Night Shade's hideout. Peering around the corner, she saw that the coast was clear.
So far, so good, Sunset... she thought to herself as she entered, sticking to the shadows.
Mare-Do-Well followed the passageway, eventually stumbling into a large hall. In the middle of the hall was a collapsed fountain, surrounded by a series of cluttered gravestones. Along the sides of the hall were a series of adjacent hallways, and at the opposite end, two staircases leading in different directions. A few guards were stationed on the ground floor below and the second-floor walkways.
Mare-Do-Well dove behind a pillar, peeking out from her hiding spot as she surveyed the area. Underneath her mask, her brow furrowed. Guards won't be a problem... but this place is bigger than I imagined. It's gonna take a while to search this place, and I don't have a lot of time before those tranquilizers wear off and the guards back there figure out what happened. Her eyes fell on a lonely patrol slowly approaching her direction.
Why don't I just ask him where Dusty Runes is? Smirking, she crept up to the corner, loading her crossbow with a tranquilizer dart. Crouching down, she waited for her target to approach.
As the guard rounded the corner, he was suddenly grabbed. Before he could scream, Mare-Do-Well covered his mouth and dragged him away. As he struggled to break free, he was pinned against the nearby wall. Mare-Do-Well glared at him through her eye lenses.
"Don't even think about screaming for help, unless you want me to break something," she whispered menacingly. "Got it?"
The stallion gulped and quickly nodded, sweat pouring down his forehead. "Got it," he whimpered through Mare-Do-Well's forehoof.
"Dusty Runes, light-yellow earth pony in a brown cloak, Daring Do's partner. Where is she?"
"Uh..."
"And it would be in your best interest not to lie to me," Mare-Do-Well growled as she pressed the guard harder against the wall. "Because I'll find you and hurt you if you do."
"Eep!" The guard's eyes widened in fear and he began shaking uncontrollably. "O-okay! That brat... she's in one of the storage rooms! Second hallway on the left, past the corner, last door on the right!"
Mare-Do-Well paused for a few moments. "You sure about that?" she asked. "Because I don't take too kindly to liars."
"No-! No, wait-! I-I mean yes! Yes!" the guard cried out. "She's there, I swear to Celestia!"
"Well then..." With a sly grin, Mare-Do-Well raised her crossbow. "Thanks for the help."
"Wh-what are ya doin-?!"
"Good night." Mare-Do-Well shot a tranquilizer at the guard's neck, putting him to sleep in an instant. Setting him down behind a nearby plant, she quickly made her way to the left-side walkway. Keeping low to avoid getting seen, she made her way down the path.
As she reached the first branching hallway, she spotted the shadow of an approaching guard. She waited at the corner for her target before knocking him out with a swift swing of her forehoof. Quickly looking around to make sure she didn't attract any unwanted attention, she dragged his body into a nearby closet and shut the door.
Mare-Do-Well soon arrived at the hallway leading down to where Dusty Runes was being held. After a quick peek around the corner, she made her way forward, stopping at the corner. Keeping her head low, she spotted another guard. This one was leaning against the wall, glaring at the door in front of him. Hanging from the side of his cloak was a keyring with a single key.
"You want me to smack you again?!" he shouted at the door. "Knock that crap off!"
"Oh, I'm sorry! Am I annoying you?" a female voice sarcastically answered. It was followed by a loud clanging sound.
That must be Dusty Runes! Mare-Do-Well grinned underneath her mask.
"Keep that noise up, and I'm personally dragging you to Night Shade!" the guard yelled, pounding his forehooves together.
"I don't know anypony named Night Shade! So why don't you just let us go?" Dusty Runes replied in a sing-song voice.
Underneath her expressionless mask, Mare-Do-Well was puzzled. What does she mean she doesn't know somepony named Night Shade? She's the one holding her hostage... wait a minute... Her eyes widened as she suddenly realized what Dusty just said. Did she just say 'us'? Is somepony else with her? Her eyes narrowing dangerously, she jumped out from the corner and fired her crossbow.
"Oh, so you're playing stupid now, is that-?!" The guard winced as the dart connected, and he held up his forehoof to his neck. "What the...?" he muttered, before slumping over and falling asleep.
Mare-Do-Well moved towards the guard, the glow of her horn hidden by her fedora as she levitated the keyring from his cloak. As she stuck the key in the lock, the clanging from the other side of the door died down. With a click, the door unlocked, and Mare-Do-Well slowly pushed it open.
The door swung open, revealing a short light-yellow earth pony, her brown mane unkempt and her light-brown cloak dirty and ripped in a few places. She was carrying a metal pipe in her forehooves, standing on her hind legs next to a shelf.
"Yeah, bring it on! Do your wor..." Dusty Runes fell silent as her eyes fell on the costumed pony in front of her, and she dropped the pipe. "Who... who are you?" she asked nervously. "What happened to..." Her voice trailed off as she spotted the sleeping guard pony behind her rescuer.
"Don't worry, Dusty Runes," the costumed mare reassured her, crouching down to the earth pony's level. "My name's Mare-Do-Well, and I'm a friend of Daring Do."
"Daring Do...?" Dusty's eyes widened, and a grin formed on her face. "So... the Relic...!"
Mare-Do-Well nodded. "Princess Twilight has it. It's safe for now."
"That's good to hear!" Dusty squealed, clapping her hooves together in delight. Suddenly, her excitement grew into concern when she looked past Mare-Do-Well and realized something. "Wait a minute... where's Daring? Is she...?"
"She's not with me, she got beaten up pretty badly," the costumed mare replied. Spotting the worried look on Dusty's face, she quickly added, "But don't worry. A friend of mine's looking after her as she recovers. She's in good hooves, you can be sure of that."
"So she's okay!" Dusty jumped up and pumped her forehoof into the air in glee. "Awesome!"
Mare-Do-Well smiled as she watched Dusty jump up and down. "Okay then," she said, raising a forehoof. "But I've got something to ask you."
"Really? What is it?"
"I overheard your banter with that guard, and you said 'Let us go.' Is there somepony else here with you?"
"Oh, yeah!" Dusty turned around and held her forehoof up to her mouth. "Hey Moon Dusk!" she called out. "Somepony's here to break us out!"
Underneath her mask, Mare-Do-Well's eyes widened. Wait... 'Moon Dusk'?! She doesn't mean-?! She was snapped out of her thoughts when she saw somepony emerge from behind the shelf nearby. She stood up slowly as she recognized the dark grey unicorn standing in front of her.
"Hmm..." the unicorn muttered, looking over Mare-Do-Well. "The Mysterious Mare-Do-Well, I take it? I've heard quite a bit about you. My name is-"
"Moon Dusk..." the costumed mare whispered quietly.
Dusty and Moon Dusk both gasped. "Hold on... you two know each other?!" she blurted out, pointing her forehooves towards the two ponies.
"No..." Moon Dusk answered, his eyebrow raised in puzzlement. "I don't believe we've met before."
"Actually... we have," Mare-Do-Well said. "After I was dismissed by Princess Celestia, I lived with you for two years while you tried to help me sort things out." Using her forehoof, she slowly lifted her mask. Moon Dusk gasped in disbelief as he recognized the all-too-familiar yellow and red mane.
"Is... is it really you...?" he whispered, his eyes watering.
"Yes..." the unmasked Mare-Do-Well answered, shaking her mane loose, a warm smile on her tear-soaked face. "It's me... Sunset Shimmer."