"Guard, is everything ready?"
"Yes, Captain."
"Security perimeter established outside the office?"
"Yes, sir."
"Good, we're going in now. Help me up, one of you."
--------------------------------------------------------------------------------------------------------------------------------------------------------------
Levitating a gas lantern with dark brown unicorn magic, Captain Gibraltar received a lift into the hole leading down a secret passage into the mountain Canterlot and its castle was built upon. The Captain knew of the mining that took place in old times - and the honeycomb of mine shafts and pits now mostly used by bat ponies - but had no idea that the enemy Agents of Chaos had been using them as their secret headquarters. This showed the Captain the deficency of the current surveys, but due to lack of staff was not able to do much about it until the later Changeling invasion once again highlighted the problem of the deficient surveys.
The secret passage was low, and Captain Gibraltar had to duck down to prevent the tip of his horn poking into the rocky ceiling. Two Upper Class Guards, both pegasi, were able to wing-boost themselves into the hole and followed the Captain of the Guard into the secret passage. The passage twisted and turned a few times before emerging onto a small landing, barely big enough for the three Guard stallions to stand on, directly facing an old mining elevator.
Gibraltar immediately moved over the controls, muttering something about how the Agents must've been able to keep the old equipment working. He immediately notices two different controls - a switch that opened and closed the cage that would be used to ascend and descend the shaft with, and two words scratched into a panel with a row of buttons: "Shrine" and "Office".
"Like a work elevator." Captain Gibraltar comments as he squints into the somewhat rusty but still solid cage. "There's probably other places this goes, but we'll check the two associated with the words right now. Everypony into the elevator cage."
------------------------------------------------------------------------------------------------------------------------------------------------------------
The lever to open the door leading into the cage opens with only a hint of reluctance when pushed by unicorn magic, and the two Upper Classes cautiously proceed into the cage first, Gibraltar quickly behind them. The lever is pushed shut again and the button labeled "Shrine" is depressed with a hoof. The cage shudders and slowly begins a clanking, creaking descent into the mountain, a chill beginning to spread over the ponies.
"All systems go... wonder what's keeping this running, sir?" one of the Upper Classes comments to Captain Gibraltar.
"Some kind of enhancement on the mechanisms, no doubt. Only unicorn magic could do that, though." Gibraltar replies, eyes narrowing in contempt as he speaks. "Aten was already a traitor and hypocrite, is he a sadist too?"
"I think we'll soon find out, sir." the other Upper Class answers as the cage screeches to a stop in front of another tunnel in the cold rocks.
-------------------------------------------------------------------------------------------------------------------------------------------------------------
The cage door is opened by the Upper Class Guard that had spoken first previously, then tentatively that pegasus steps out of the cage and tests the rock in front of him, just in case there were any traps triggered by hoof pressure waiting for the search party. Only when confident that no traps were waiting do the searchers step out into the tunnel.
A quick check determines the tunnel directly facing the elevator only goes a short distance into the rocks, but turning around reveals a passage leading away in a different direction. Following this passage through several twists and turns, the searchers open into a small, musty chamber, barely big enough for the three stallions to fit into.
"Is this the shrine?" Captain Gibraltar asks amist the echoed shuffling of hooves.
"Must be sir, look at the shelf." an Upper Class answers, pointing toward the far wall of the chamber. On a natural rock shelf jutting out from that wall is set a pair of candles, partly melted from previous use, and a picture set between the candles. When Gibraltar moves his lantern closer to the shelf, he realizes the picture is of a statue in the statue garden - the same "Statue of Discord" Princess Celestia was so worked up about!
"What is with this statue, that the Agents of Chaos would build a shrine to it? Is there some connection to 'the chaotic one' they kept talking about?" Gibraltar asks in a great deal of puzzlement, squinting at the picture in the darkness.
"Sir, there's some kind of parchment near your forehooves!" one of the Upper Classes exclaims, and Gibraltar looks down to see the subordinate was correct, carefully lifting up the parchment using unicorn magic.
--------------------------------------------------------------------------------------------------------------------------------------------------------------
The unicorn Guard Captain turns the parchment over several times as he looks it over, and after a minute his eyes go wide in surprise. At the same time, a small gasp echoes inside the chamber.
"Sir, what is it?" one of the Upper Class Guards beside him asks.
"This is a meeting transcript with Princess Celestia, an old one." Gibraltar answers, the shock still in his expression.
"How old are we talking, sir?" the guard who spoke previously asks again.
"The transcript refers to Aten as a Lieutenant, so it's a number of years old. It looks like it occurred during his 'equal pegasi rights' campaign..." Gibraltar speculates.
"The same one that caused Celestia to promote him to Lieutenant Captain?" the other guard escort pipes up.
"Yes, and this is very revealing on how he got he far as he did. You can read for yourself, if you want." Gibraltar offers.
The two Guard Upper Class escorts squint at the old parchment in rapt curiousity, beginning to read at the alternating conversation between Princess Celestia and then-Lieutenant Aten, Celestia speaking first:
"Lieutenant, I am certainly aware of the pride pegasi in general and pegasi stallions in particular have of their military heritage in the Equestrian state. But I will simply not tolerate your false and unfounded accusations of discrimination against pegasi in the service! If there are specific complaints you wish to address, you can have confidence that the Captain of the Guard will listen to and address your problems. I do not see the need for this meeting, what you are seeking can be reached in other ways."
"Your Highness, I asked for this meeting because I wanted to tell you something directly. I know that you keep something, or someone, imprisoned in the castle's statue garden. And I know a way to release that something from that imprisonment."
"... You know something is there? Whisper what he is in my ear, and I will know whether you speak true or not."
(unintelligble whispering)
"Your Highness, I know from the shock on your face that I am speaking true. And that's why unless I get exactly what I want, I will make every effort to release that being imprisoned in the statue garden. Does the Princess understand?"
"... Yes, Lieutenant."
----------------------------------------------------------------------------------------------------------------------------------------------------------------
The shock on Gibraltar's face is now shared by the escorts reading the parchment - except for the "Eternal Night", they could not imagine a scenario where Celestia was scared enough to submit to that kind of blackmail. All eyes turn back up to the picture in the shrine.
"Does the transcript say what Aten whispered into Celestia's ear, sir?" one of the Guards volunteers.
"No..." Gibraltar replies numbly, reaching a forehoof in the direction of the shrine's picture.
"What is it about this 'Statue of Discord'?!" the Guard Captain continues on in anguished confusion. "Why was Celestia so obsessed with this same statue this morning? Why is there a picture of it here at all, seeming to be worshipped by the Agents of Chaos? Is it related to that threat Aten used to get his way, and build his rebellion, all those years ago? All these questions, and no answers..."
"I feel, sir, that Celestia knows something about that statue we don't and that she won't tell us what it is." one of the Guards comments.
"I hope you are wrong, Guard, but fear you are right." Captain Gibraltar grimly states.
Indeed the guard was right, and Captain of the Guard Gibraltar would live to both see and regret the truth of that statement. Nopony except Princesses Celestia and Luna knew it at the time, but the presence of the Agents of Chaos was linked to an even greater threat to Equestria's peace and harmony, and as it turned out would help bring another mighty threat into Canterlot. The clues left in the crypts of chaos would be ignored, and great threats would attack Equestria because of it...