"Oh, Spike," Twilight said. She was frowning—too many ponies along the way had misidentified her Star Swirl the Bearded costume—but tried to keep it out of her voice. "It looks like we're here—"
Twilight turned. A dark figure loomed over her, face shadowed by the moon that framed it. It shined in the starlight, glistening, chitinous. A huge sharp and twisted horn menaced her, and the creature hissed at her with glowing green eyes and a mouthful of fangs.
Twilight screamed and punched it in the face with a hoof. It fell back against the bushes, and Twilight gasped for breath from the sudden shock.
"I really should have expected that," it said, with a familiar voice. It straightened up again, rubbing a hoof against its face where Twilight had walloped it.
"Liminal?" Twilight said. She looked again. Heat crept up her cheeks as she saw the familiar shape of the muzzle under whatever was providing the black shell, and the same unhealthily slim figure. Some trick trick made the hair membraneous and patchy, but the way it hung loosely around her head was the same, and the diaphanous wings that jutted up from her back could easily be a costume piece. "Oh, I am so, so sor—"
"Don't be," Liminal interrupted. She blinked a disconcertingly green eye rapidly, then rubbed at it more with her hoof. "I was the one who couldn't resist giving you a scare. And I'm sturdier than I look." She made a dismissive gesture.
"But I..." Twilight said, and then Liminal gave her an unimpressed look with her eyes half-lidded, and she gave up trying to protest. "You're sure you're all right?"
"Yes, yes, I'm fine. How do you like my look as a changeling?" Liminal said. "Am I sufficiently terrifying and-or seductive?" Liminal gestured loosely at herself with a longer-than-usual leg and turned in a tight circle.
"Limmy, you're less 'seductive' than I am," Twilight said, and she half-suppressed a snort of a laugh. "But you are scary. That old mare's tale—aren't changelings supposed to look like the ponies they're imitating?" She tilted her head to look closer at the holes through what must be short stilts. "Why so... insectile?"
"Don't tell me you're a trypophiliac, Twilight," Liminal said, nudging her muzzle away. "It's one of the more classic interpretations, actually. A few of my friends and I got together to coordinate looks for the night, and this is what we settled on. And isn't Star Swirl a little obscure, even for you?"
"Thank you for recognizing the costume," Twilight said. "Unlike some dragons I could name." One of her ears flicked.
Spike shrugged and stuffed another handful of hard candies, wrappers and all, into his mouth.
"And Star Swirl the Bearded is hardly obscure!" Twilight huffed. "He was—"
"—completely unrecognized by a cross-section of average ponies from this town?" Liminal interrupted. "But just a moment. I need to get some of that horrible festival food." She strode away through the crowd. Her extended legs elevated her from merely tall to Princessly heights, and ponies readily parted around her. Some shrieked or giggled nervously or both as they came face-to-face with fangs and black chitin.
Twilight hurried after her, nearly dragging along Spike, and caught up in time to see Liminal efficiently chewing her way through an entire spiral-cut deep-fried potato. Three more floated along in the green aura of her magic.
Twilight did the math in her head and edged away from the slightly-too-eager pegasus pony potato purveyor's pugnacious potato presentation. "Just one of those must be a thousand calories. How do you stay so skinny?" It was blunter than she'd have been with her other friends. Liminal was sharp-edged, but she allowed the same from those around her—sometimes welcomed it, even.
"It's in my nature. I can never gain weight. Oh, these are awful," Liminal said happily as she stuffed more potato into her mouth. She chewed vigorous and swallowed and Twilight wondered how the fangs stayed neatly in place even while eating. "So much grease. Want one?" Liminal said, and Twilight shook her head firmly as the taller pony tried to proffer a potato at her.
Spike raised a hand to take one, and Twilight tried not to sigh. It would at least mean his dinner wasn't only candy.
"Hey, Twilight!" squealed Pinkie Pie as she bounded up in a chicken costume, loosely followed by a collection of foals in all shapes, sizes, and outfits. "Look at my—" She looked up at Liminal, then further up to see her eyes, then back down to see the fangs again, and then shrieked and jumped into the bushes. She left behind, in midair, bags that scattered candy everywhere as they fell.
Instant chaos resulted among the foals as they scattered to grab candy. Liminal hissed at them like a predatory cat but didn't move, and some darted nearly into her reach to grab a piece before scrambling away again.
"Oh no!" Pinkie Pie called from the bushes, just her chicken-beak protruding. "First Kevin and now you? Pretty soon there will be changelings everywhere! Replacing princesses! Sneaking into weddings to feed on the bride and groom! Painting bright colors on mooses just because they can!"
"I do hope there will be no replacing of princesses," said a short-maned, dark-coated unicorn mare in a rather nice witch costume as she navigated her way between the racing foals. Her eyes were on Liminal.
"I will endeavor to avoid moose-painting," Liminal said in a dry tone. "And everypony knows the plural of 'moose' is 'meese', anyway."
In the bushes, Pinkie Pie gasped dramatically.
"But Shooting Star, it's nice to see you again," Liminal said, and she offered the smaller mare a leg with holes in it. "Have you met Kevin? He's doing the whole bug-pony thing too, and I understand he's running some of the entertainment. Something to do with pumpkins and trebuchets..." She frowned minutely, looking off into the distance.
"The plural of 'moose' is 'moose', Lim," Twilight said.
"Meese," Liminal said.
"Moose!" Twilight said.
"Meese," Liminal said.
"Moose," Twilight said.
"Moose?" Liminal said.
"Yes, moose!" Twilight said.
Liminal considered for a long moment, then took a bite of one of her still-floating potatoes, chewed, and swallowed. "Meese," she said.
Twilight sunk her head into one hoof, and watching them, Shooting Star made a noise suspiciously like a laugh muffled by a tightly-shut muzzle.