Unease filtered through Celestia’s bones as she walked away from L-55, the echoes of Theta’s mad cackling still echoing through her mind. It was a sensation almost entirely foreign to the nigh-ageless Outsider, and it took all of her not inconsiderable mental discipline to not instinctually squash it out of her awareness.
Because anything that could make her nervous was something that required her utterly undivided attention, and she needed that sensation there to keep her on-task and focussed.
Not that it was helping, however. Despite her innumerable years of experience dealing with existential threats to the Exterior, she was at a total loss for a solution to her dilemma. Beyond interrogating each and every resident of the Exterior, there was little she could do to determine if Theta was acting alone, or had collaborators.
The mere idea was nigh-unthinkable. The mare was psychotic, unhinged to the point of delusion. The only reliable fact about her was that she had brutalised or killed every Outsider sent to stem the tide of bodies that followed in her wake. Nopony would have been able to work with her without fearing for their own lives, waiting for that inevitable moment when Theta deemed they had outlived their usefulness.
Or, more likely, the moment when Theta would decide that they were the easiest target for her latest boredom-alleviating murderspree.
According to official, public record, Theta was directly responsible for the deaths of twenty-three Outsiders since her recovery, four years ago. The number of unsolved Outsider deaths that were directly or indirectly connected to the mare, however, spanned into the tens of thousands over a period spanning decades. None of them were substantiable, of course, otherwise they wouldn’t have been sending mere Operations teams to bring her in. They would have been throwing Detachment Devices at any world she was even suspected of being on, and damn the consequences.
And of course, she couldn’t be working with someone stronger than her, since, as always, she would get bored, attempt to murder her ostensible ally on some spur-of-the-moment urge, and get obliterated for her trouble. And since Theta was still alive, the likelihood of that particular scenario was effectively zero.
Which left either a weaker ‘ally’ who was exceedingly capable at avoiding being the next target of Theta’s random killings, a stronger ally with considerably more restraint than Theta herself, or Theta was working alone with a level of foresight far beyond what anyone had given her credit for.
All options seemed equally impossible.
In everypony’s experience, Theta was not a calculating mare. She was random and impulsive. Prone to gleefully random bouts of violence and mayhem. Planning was not something she did.
As she slowly passed through each of the seals separating Containment from the greater Exterior, Celestia came to consider another, singularly frightening possibility:
Somepony may have found a way to control Theta.
She shuddered at the possibility, pausing just beyond the final seal as she waited for her spell suite to reassert itself and reconnect her now that she was clear of the thaumic field discontinuity induced by the Containment seals. One by one, the spells came back online, streams of tabulated data once again streaming into her peripheral awareness, collected from tens of thousands of quasi-sentient autonomous information-gathering spells.
Her sense of unease lessened slightly as the familiar comfort of sheer, unmatched awareness returned to her. A cacophony of voices accompanied it, communications spells reasserting and connecting her back to the myriad networks she had direct or indirect involvement in. A short mental directive relegated the majority of them to low-level awareness, while bringing a secure high-level command-and-control feed to the forefront of her attention.
“This isn’t a minor breach, you realise,” a voice said, inserted directly into her auditory nerve by her spell suite. “That section of the Armory is subject to the most sophisticated security interlocks we could devise. If somepony can just walk in…”
“Alpha here,” Celestia subvocalised, spells capturing the words for transmission. “What’s going on?”
“The Queen in Pink returns! Finally! We have a situation!”
“I keep telling you,” another voice interrupted, “this is not a major issue. We know exactly where the thieves are. We can stop them before any damage is done.”
“You should be more concerned about this!”
“Forgive me for having faith in our security team to interdict two ponies.”
“Anypony going to fill me in, or are you both going to keep arguing away?”
“One of the secure vaults in the Armory has been breached. An explosive was taken.”
“By whom? What was taken? How long ago? Details, Solaris!”
“Two ponies, looks like it was an inside job. They took a thaumonuclear device.”
“Do you know who exactly?”
“Team Fifteen. A Whooves and a Sparkle.”
Celestia stopped mid-stride, surprised. “Are you sure?”
“Absolutely sure. We have a breach somewhere, obviously, since access permissions don’t include a Sparkle from Fifteen.”
“There’s no breach. Fifteen’s Sparkle has access to the Armory, actually.”
“No she doesn't,” the second voice challenged. “There is no entry for a Sparkle from Fifteen in the logs.”
“I know that, Anna,” Celestia said, mildly irritated. “This particular Sparkle doesn’t need any entry.”
“Would you stop being so gods-damned coy about this, Alpha?” Solaris demanded. “A stolen thaumonuclear device is hardly a small problem!”
“Fifteen’s Sparkle has my personal dispensation to access the Exterior in its entirety. She is working for and loyal to me personally. I trust her, and trust that she has need of the device.”
For a moment, she pondered what possible need her trump-card Insider could have for the weapon, considering that Twilight hadn’t been told about the existence of such powerful devices, at least by her.
“And when did you feel like informing the rest of us about your little sleeper agent?”
“Never. The only reason I’m telling you now is because otherwise, you’d have her arrested and mind-read. On that topic, have your guards stand down. They are not to be interdicted.”
“Are you mad?”
“I am quite sure plenty of ponies think so, but that’s immaterial. Grant them passage.”
“Fine. Done.”
“So,” Anna began. “Did you find out anything useful from the Rogue?”
“Theta is about as comprehensible as she usually is. Which is to say, not very. Cryptic riddles, and lots of her trying to screw with my head. Nothing substantial or actionable.”
“Well, that’s entirely unhelpful.”
“I thought much the same thing. Short of a direct mind-read, we’re not going to get anything useful from her. And I doubt anyone working for us has the power to punch through Theta’s mental fortitude.”
“So, what’s the plan?”
“I don’t have one, so we’re just going to have to wait and see what pans out. I have a few theories, but no evidence to support any of them, short of interrogating everypony on the Exterior.”
“That sounds like a plan,” Solaris said.
“We are not interrogating everypony on the Exterior. That’s so far beyond practicable it’s not funny.”
“And I’m not laughing. If that’s what it takes to find out what that madmare is up to…”
“By all means, Solaris. If you can find a way to organise untold trillions of ponies and have them submit to mind-reading, be my guest.”
“I’m sure we have a large enough guard contingent to manage a sectional sweep…”
“Solaris, be sensible. Alpha’s right. We don’t have the pony-power to interrogate everyone, and we have no leads. All that’s left is to wait and see what happens next.”
“That’s horseapples. I am a stallion of action! I will not stand around-”
“You’re full of hot air is what you are.”
She took a moment to appreciate the pointed silence that greeted her over the spellwaves. While she respected Solaris as a commander and a tactician, he was a lackluster administrator, all too eager to jump on the aggressive, militaristic solution. And as much as she loathed to antagonise any of her colleagues, it was occasionally necessary to get the war-stallion away from his fixations.
Her awareness shifted, tracking and positioning data called to the forefront of her perception as she called for information on Twilight. Currently, the Insider was being led along at full-pelt by Fifteen’s CO, the stolen bomb dutifully following behind the duo in the grip of Twilight’s magic as they headed towards Habitation. She was largely unconcerned about the device itself, since it was impossible to arm it within the Exterior. Not that Twilight would know that, of course, but it would provide rather telling proof of her treachery if she were to try.
As it were, Celestia continued to watch Twilight as she and Walleye rounded up their teammates, curiosity piqued as the five ponies made a rapid beeline towards the Exterior’s Gate array. Minor alerts pinged in her peripheral awareness as Operations interlocks detected the weapon passing security boundaries, which she dismissed offhoofedly.
An instant later, the entire Gate array dropped clean out of her awareness.
“What the…?”
She wasted no time, sending packets of energy to the myriad of observer spells responsible for that area, attempting to reassert her observation coverage.
“Alpha, what did you do?” Anna asked, audibly concerned. “I can’t see anything near the Gates.”
“That’s not me! Solaris! Are you up to something?”
“Not me. I blame your little sleeper agent. No coincidence that spell coverage dropped out just as she entered the area!”
“No, it’s not her. She doesn’t have the ability to cause an outage on this scale.”
Fragments of information began to filter back into her awareness, almost all of them tinged with interference, providing no clear picture on what was going on. She brought the PA network bridge forward, issuing a command.
"Security breach. All teams stand by for immediate action.”
“Security breach?” Solaris hissed.
“I have no idea what’s going on. Something is actively interfering with my spell coverage. I can barely see anything through it.”
“At least you still have a bit of coverage. My spells are all completely gone.”
She picked up her pace, heading towards Operations. While her own observer spell swarm was largely ad-hoc and provided complete coverage mostly through sheer force of their owner’s will, she knew that Solaris’ versions were hardened and redundant to the point of paranoia. Anything that could manage to irreversibly knock his coverage out was a threat that needed to be dealt with quickly.
“Do you have any contact with security teams at the Gates?”
“No. I’ve got nothing from that entire area.”
“Featherballs,” Celestia swore, breaking into a gallop, pulling what little diagnostic information she should from the surviving observer spells. Gate activation logs began to filter back into her awareness, distorted from interference. “Solaris, whatever guards you can reach, get them over to the Gates now. Full containment!”
“On it!”
A fragmented Gate activation alert popped forward, which she reflexively directed to her PA bridge.
"Security breach, Gate Three.”
“Anna. Start evacuations of all civilian areas closest to the Gates. Somepony, or something hostile is on the Exterior.”
Silence greeted her, further activation alerts popping into her awareness as she ran, which she forwarded to the PA bridge as she was able to piece them together.
“Anna, are you there?”
"Security breach, Gate Six.”
“Solaris, do you read?”
“Yeah, I’m here. I’ve got guards mobilised.”
"Security breach, Gate Two.”
“What in Tartarus is going on?”
“I don’t know. I’m getting a lot of fragmented information, but I can’t tell anything beyond the fact that something is coming aboard the Exterior.”
“Security breach, Gate Nine.”
“Security breach, Gate Fifteen.”
“Security breach, Gate One.”
“Solaris? You read?”
She cried out as the entirety of her extended perception dropped out of her awareness, leaving her blind to anything going on beyond the corridor she was now in. Communications spells flickered and died in her mind as a blanket of interference flooded the spellwaves around her.
“Theta,” she growled, pulling long-disused combat spells from her memory, rushing as fast as her legs could push her towards Operations.