Under cover of darkness, Twilight crept on her belly forward from one cover to the next. While the bushes nearest to the shack were trimmed away, that effort didn't extend very far. That was an intentional decision. If it looked too manicured, that would draw attention, so the space around the shack was allowed to grow as it pleased, with just the immediate space around the shack kept clear for visibility. That worked to her benefit as she crept closer in the chill of the night.
She could see her target. More specifically, she could make out the basic box shape of the building. She couldn't see anything inside it, or make out many details, but she was close, and that would have to be good enough. "Ping," she quietly whispered to herself. Her horn glowed for a brief insignificant moment, no more than a firefly's excited illumination.
Without sight, she could see. Her magic began to bounce back towards her, painting a picture of the small building, specifically its electronic pieces. She felt silly, having never scanned the building for such things before. Then again, it simply just hadn't been her job before. She'd come up to repair the camera, and she knew exactly where that was, so why would she be scanning around?
So she hadn't, until that day. The mechanisms for the elevator echoed her magic. She felt their familiar presence. The camera she knew about, check. There was the faint imprint of what allowed the lights to work, even if they were rarely used. They sure weren't working right then, only darkness there.
It was a good thing most humans didn't really think about unicorns. The ones that designed the security weren't told about it, so none of that security reacted to her scan. All the mechanisms she expected was there. No second camera? She hadn't really expected one anyway. But it was worth looking.
And anything worth doing was worth doing well. She knew the camera inside and out, but the elevator mechanisms she wasn't nearly as familiar with. She began prodding about with a fresh pulse. It would have been a lot easier, and faster, if she could put her eyes and hooves on it directly, but that was clearly not an option. She stuck out her tongue mildly as she tried for a better angle by thrusting her head up and to the right. One wire, two wires, coming together to... And that vacuum tube... It all came together...
It was a camera, a small one, a crude one. It probably gave a grainy picture at best, black and white possibly. She couldn't tell from her magical radar too much besides that. A backup camera of sorts? But she had to disable it, regardless. Or did she? They'd come to repair the main camera even if the secondary was working. The quality it made couldn't possibly be good enough... It did mean she'd have to avoid it too... Fortunately, it was still dark.
Applejack tapped at the ground slowly. "How long does it take fer a unicorn to do what she's doin'?"
Daffodil quirked an ear. "Ask a unicorn?"
"If we had another around!" Applejack threw up her hooves, but no second unicorn materialized. "Well, that didn't work... Hey, Giddyup?"
"Yes?" Giddyup was facing the hut, still as a statue.
"Yer a robot, no offense or nothin', but can ya see in the dark or not? Ain't sure, truth told." Applejack laughed nervously as she admitted her ignorance.
"No offense taken." He was a robot. That wasn't much a fact worth arguing in its truth. "My ability to detect light in small amounts is not that different than yours."
"Huh..." Applejack peeked up at him briefly. "Yer lookin' awful intense if ya can't see nothin' either, then."
"I am concerned."
"Yeah..." She sat and joined in the intense staring into the dark that gave her not any hints of Twilight's progress. "She's a clever mare, but she can...I jus' hope she's alright." She jumped at Stan's hand on her shoulder. "What?"
"She'll be fine." Stan was crouching, gun at a passively ready position, directed forward, but not raised. "Ah figure. Sounds like she was one of the head mechanics of the place."
"She sure is! Um..." Applejack looked around slowly. "Where's Aunt?"
Stan threw a thumb over his shoulder. "Hiding. She's a dear, but also basically half made of fire, which makes her pretty bad at being sneaky, all told. We decided it'd be better if she laid low, and way further back."
Applejack huffed. "That has to be even worse fer her. She can't even see how we're doin'."
Giddyup swung his head down towards Applejack, popping out of the darkness suddenly. "I cannot confirm that."
Applejack jumped. "Stop surprisin' me! Ah swear, ya stallions are aimin' to put me under... What can't ya confirm?"
Giddyup sat down, head withdrawing back into the darkness. "I do not know her specifications. Her visual acuity may be different than mine. Maybe she can see. Maybe she lost visual senses before I did. I cannot confirm this."
Stan knocked once on his metal friend. "Ain't worth worryin' 'bout. Let's just be quiet and wait for sounds of trouble, or Twilight coming back."
A low hiss reached them. Daffodil spotted the source but managed to resist a yelp, instead stomping. "Molerat!"
Skyline was there in an instant, cutting into the worryingly furless creature in a deadly arc. "They tracked us down?" But he didn't see any others. "Looks clear..."
Applejack perked an ear. "Hey... you got slit eyes and they kinda shine... you better in the dark than we are or not?"
"Hm? Never compared... I see as good as I see..." He sheathed his blade at his belt. "From the way you've been talking though... Sounds like you're getting a taste of how it usually is for me."
Daffodil slapped the side of Skyline. "Ha! So you can see in the dark. That's actually kind of... neat. So how's Twilight doing?" She pointed off into the dark in the hopeful direction of Twilight. "She alright?"
"We just went over this." He sank next to her. "She's too far away. She's a Twilight-colored blob in the middle of other blobs. I don't see anything running, or hear any gunshots, so that's good, right?"
Applejack pulled the front of her hat down. "Shoot. He can see, but not so good. Still... if ya see her actin' funny, let us know. We'll just have to have some faith in her."
She was fairly sure which way both cameras were facing. She inched her head upwards, straining to get a view on either of them, even if she didn't know what the second looked like. She figured her odds were low, but no reason not try look for it as she peered into the darkness.
Which was the problem! The area around her at least had the stars above for some dim light. Not much, but so much better than the gloomy nothing that was inside that shed. She had to see the camera to actually influence it instead of casually feeling for it. She was just making little flashes that could give her away if they weren't mistaken for a firefly or a lightning bug.
Wait...
Twilight threw a hoof in the air with a realization. Her horn glowed steadily as she worked a new magic to create more light. She did not attach the new light to her horn, instead spreading it out in fitful flickers. Imagine the surprise, possibly delight, as 'fireflies' drifted in through the opening they had poked in the window before. Nopony reported that one missing pane of glass, or at least nopony, had fixed it yet. Maybe they thought it lent to the atmosphere of it being a run-down shack? Either way, it let her magic lightning bugs drift in, glowing and flashing in semi-random starts.
The cameras weren't that good, even the main one. They'd see the flashes, but not be able to see the insects that made them, or the lack of insects. Just sparkling flashes that were entirely normal... And let her see. The flashes of light made the interior past the glass brighter than the outside for little snatches, which let her see the camera, watching balefully.
She grabbed the cord that ran from it into the wall, getting a good arcane grip as the flashing faded away, but she had a grip. With that, she could continue without seeing. She ran her feeling 'fingers along the cord, tongue extended with thought. Yes, she knew that cord... Right... there. She pressed her magic into the thick barrier. Working blind wasn't easy, or graceful, but she was doing it. She felt a change. The wires, she had reached them properly. With a jolt of power, she felt the power react in kind, then sputter and die.
She had forced it off. It could easily be turned on. It was just a button! A pity that button was on the outside. They'd have to come up to press it. She let the magic fade away and slunk through the grass and brush. She couldn't be sure if the second camera had been turned off, and what direction it was still watching, if it was still watching. She had to assume everything was being monitored.
"Overmare!" A pony stood at attention, one hoof raised in salute. "Issue with the security camera. Permission to repair?"
Overmare Mare hiked a brow. "Why are you asking? Of course, fix it."
"The repairs require leaving the vault." The guard pointed up at that unseen place. "The technician says it should be simple, but we need permission to operate the lift, ma'am."
Overmare Mare sighed heavily, eyes mostly closing. "Go ahead. The gate must be kept secure!" As soon as the guard scampered off, Overmare Mare went to a console and tapped at its oversized keys. She drew up the view of the second camera, grainy but functional. "Hm..." She didn't see anycreature lurking about... "Let's rewind..." She hit the rewind button and things went backwards, though it was hard to tell. Most of what was on the screen was still.
Until flashing. "Hm?" She stopped the rewinding quickly to see fireflies sparkling in the shack. "Ugh..." She'd have to request that repair technicians hurried up and fixed that window. It had seemed harmless to leave it alone, but... "We can't have bugs building nests or whatever else in there..." The idea of, say, a hornet's hive right there... That would be very inconvenient for any repair team sent up there. "An Overmare's job is never done." She grabbed a clipboard in her hooves and wrote with a pencil in her mouth some new duties that needed doing. "I will see it done."
By which she meant she'd assign ponies that were good at the tasks to get it done. She was a manager, so delegation was a key skill, clearly. She nodded with confidence in her actions.
The vault was in good hooves, hers.