There was a short moment of blackout after Rainbow Dash touched the linking panel of the book hidden in the gilded rocket. When sight and hearing returned to the pegasus, she thought that something had gone wrong. She was sitting on the floor of the rocket with the musical lock panel in front of her, but with the sliders all reset to the bottom and behind her was the pipe organ, although the journal she’d propped up on it was absent, as was the book she’d just used. The one bit of good news was that the rocket’s door was wide open, giving her a view of the zig-zagging stone walkway that connected the rocket to the island. Curiously though, there was now a thick fog that obscured her vision beyond the second bend in the walkway. “Twilight?” Rainbow called out as she stepped out of the rocket. She jumped as the door slid shut behind her and she whirled around to give it a hard look. “Yeah, I’m glad to be rid of you too,” she said with a sneer, and then turned around and marched away from her former prison, calling out for Twilight again. “Maybe she’s down in the house cave,” she said, trying to drive off the growing concern at the lack of response from the unicorn, “Kind of mean of her to just leave me in there…” she trailed off as she reached the end of the walkway and, due to the basic nature of fog, finally saw evidence that she was not on Aitran Island anymore. The Aitran rocket had been set up at the northeastern corner of the island, with nothing but sea off to the right as one walked away from the ship and the library to the left. This rocket’s walkway terminated in a gap between two steep ridges, a short one to the left that terminated in a sharp-looking peak before plunging down into the foggy depths and a larger one that was almost a proper hill on the right. Built into the larger rock was a brick building with an arched roof. In the middle of the building’s façade was a stone door carved to look like two matching square tiles with a flower-like pattern. To the right of the door was a panel with five sliders, a speaker, and a button.
“Another music lock?” Rainbow wondered, nosing one of the sliders, all of which sat at the top. A low whistling sound came from the speaker, and as Rainbow moved the slider down its track, it gave off a seemingly random collection of sounds. “Whistling, ticking, a train whistle, trickling water… What they hay?” She put the slider back in its initial spot and shook her head. “No way I’m getting past that without any clues,” she said, looking around, “so the first order of business will be getting rid of this fog so I can see!” She spread her wings and shot up into the sky, climbing higher and higher in a tight spiral until she could no longer see the ground. Flipping around, she went into a dive with her wings angled to stir up the air as much as possible without killing her speed, a standard maneuver for solo fog management. As she neared the ground, she pulled out of her dive and began flying in a tight circle to form her patented Rainblow Cyclone, good for rapid drying, trapping parasprite swarms, and especially for pulling fog banks into compact, easy-to-manage clouds. In theory at least. After a solid minute and a half of flying in circles, Rainbow had to come in for a landing before she grew too dizzy. After steadying her eyes and catching her breathe, she looked around in disbelief at the fog, which was no more or less thick than when she had begun. “Perfect,” she said sourly, “Who’s bright idea was it to make a world with weather that doesn’t respond to pegasus ponies?” She took another look around and dejectedly tucked her wings up against her sides. Fog this thick was not a safe environment for flying; it would be far too easy for her to lose sight of landmarks and get lost. Grounded, her only options were to head back toward the rocket or to follow the small valley she was in. Rainbow made the obvious choice. When Rainbow reached the point where the natural wall on her left ended, she could see a large grandfather-style clock tower ahead of her, while off to the left there was a paved path leading over a small bump and then climbing to the top of a cement enclosure and beyond and to the left of that Dash could just make out the shapes of trees through the fog.
“Trees mean life,” Rainbow said, trotting in that direction, “I hope they’re alive at least…” The land dipped as she neared her goal, but there was a set of stairs built into the side of the hill to make climbing up easier. To the pegasus’s pleasure the hilltop held not only a stand of trees, but a carpet of grass and as she walked through she spotted a small spring of water. Somepony had built a stone pool around the spring, with a small dip in the rim to allow the water to slowly trickle out and down the hill with a soothing sound. Next to the pool was a short brick tower topped with a dish pointing out toward something Rainbow couldn’t quite see in the distance and a boom pole dangling a microphone over the water. A booth stood at the foot of the tower, bearing a bronze plaque showing a water droplet and ripples with a button on a shelf below it. Next to the booth was a bench, on which sat a familiar-looking blue piece of paper, covered in meticulously written archaic letters in a blue ink that barely stood against the blue paper. Rainbow’s eyes widened in surprise; it was one of the pages missing from Archeon’s book prison. “How’d you get here?” Rainbow wondered, glaring at the paper like she expected it to answer. After a moment, she picked the paper up and put it in her saddlebag before contemplating the device in front of her. Microphone goes to the tower, she thought, so that dish is probably for sending the sound to someplace else, like a radio or something. She pressed the button and the symbol on the plaque lit up. “I’ll assume that means ‘on,’” she said as she turned to leave, pausing to get a drink from the pool before heading down the stairs.
She made her way to the stairs leading up to the cement enclosure and started climbing the stairs to the top. She found herself on a balcony next to a transmitter tower, and the air felt much warmer and drier. A low rumbling came from below, so she peered over the edge to see a deep rift in the earth that revealed a lava flow. “Yikes,” the pegasus said, pulling away from the edge. She looked at the button for the transmitter and saw that its plaque was engraved with a jagged crack with wavy lines rising from it. “Somepony must have been fascinated by sounds to go through the effort of building this just to safely listen to a dull roar,” Rainbow said, hitting the button and leaving. When she reached the bottom the stairs, she paused and looked around for new landmarks. She could see the clock and the locked building ahead of her while to her left was a large body of water and, just barely poking out of the fog bank, a set of stairs leading up to a tower that looked like it had several radio dishes on it. Glancing back, Rainbow noted that the dish on the transmitter tower she’d just left pointed toward the distant tower. “That’s the goal then,” the pegasus said, starting to spread her wings to fly to the tower, “At least to get a better idea of what to do.” She leaped into the air and flew low over the water to stay sure of her altitude, even though it took her no more than a couple seconds to cross the distance to the tower. She flew around it once to give it a close look from all angles. It was situated on a small rock of an island, with the stairs built onto the side leading to what looked to be the access shaft of an underground tunnel, complete with a hoof-operated winch-lift.
The tower itself was circular in shape, a brick and stone base topped by a round metal scaffold supporting five small receiver dishes in a vertical arrangement. Rainbow also noticed two urn-shaped sculptures that stood about half her height on either side of the walkway that terminated at the tower. The curve of the base was broken for a space between knee-height and a little above Dash’s head by a pair of stone panels bearing the same carved pattern as the door of the locked building and with handles on the inside edges. Dash grabbed one handle in her mouth and pulled, finding that the panel swung open easily, like a cabinet door. She swung the other panel out of the way as she looked inside at what was clearly a control panel. The top half was dominated a by a black glass screen, with speakers on either side. The bottom half contained two triangular button pointed left and right, then yellow five buttons bearing symbols, and finally at the bottom a maroon button with what looked like a weird capital E. Rainbow recognized the symbols on two of the buttons: the water droplet and the steaming crack. The other three were a set of clock hands, a pointed crystal stuck in the ground, and a circle with lines indicating wind blowing up from it. “Five symbols, five dishes,” the pegasus mused, her gaze drifting up the tower before heading out to gaze at the fog-shrouded land in the distance, “So there are five spots out there with microphones and I’ve found two already. And there are five sliders on that building…” She smiled at the control panel. “You give me the combination, don’t you?” she asked it, and then turned away and spread her wings. “Better go turn the other three on first.” Looking around for a landmark, she saw the silhouette of the clock tower, with the silhouette of a transmitter tower right next to it. Nodding with determination, Rainbow made the short flight over the water and landed in front of the clock.
The first thing she could tell about the clock was that it was broken. A pendulum lay on the ground in front of the structure and although she could see another one deeper inside the open tower, it was swinging far too slowly to be keeping proper time. Looking up at the face, she saw the minute hand move whenever the pendulum completed it slow arc and forced a melancholy Tick out of the mechanism. When the hand reached the 8 position, it suddenly dropped and swung free until it settled on the six and the clockwork grabbed it again. The hour hand was currently pointing at 1 and seemed inclined to stay where it was told to be. “That’s a little sad,” Rainbow said as she went over to the transmitter and turned it on, glancing only briefly to confirm that the symbol was clock hands, “especially since this thing seems to be working just fine. Ah well, moving on!”
Past the clock, the land was little more than a wide ridge between the lake and sea, curving gradually but consistently to the left. When Rainbow had gone far enough that the clock began to disappear into the fog, she came upon another urn sculpture situated at the top of a staircase leading down the seaward side of the ridge to a metal walkway that weaved through a number of large purple crystals poking up out of the water. “I bet Rarity would love these,” the pegasus said as she walked down to them, “but she’d probably have to break them down to get any use out of them.” She chuckled at the mental image of the fashionable unicorn agonizing over the dilemma of destroying perfectly formed crystals versus not being able to own and use them, but then fell silent when she heard the music. A stiff breeze, which did strangely little to the local fog, blew through the crystal field, creating eerie yet mesmerizing tones that rose and fell in random harmonies as it caused the spires to vibrate. The metal walkway Rainbow as on ended near the middle of the field where the music was the strongest, and as expected she found a transmitter tower with the spire symbol there. To her surprise, she also found a red paper sitting on top of the button pedestal. “A page for Cirrus too?” the pegasus said in surprise before rearing up to grab it in her teeth and set it down on the button to take a better look. Sure enough, it contained barely-visible text written in red ink and it had a jagged tear along one side. A missing page for each of the books, she thought as she stowed the page in her saddlebag next to the blue page, If this is a coincidence, then I’m an earth pony! Setting this new mystery aside until she could talk to Twilight about it, Rainbow turned the transmitter on and returned to the shore.
The land continued to curve around the lake until it terminated at a transmitter tower sitting behind a tunnel access shaft, which Rainbow figured was the companion for the one on the lake island. The shaft was open, and the pegasus could hear the sound of air whistling up from inside the tunnel even before she looked down the hole to see the winch platform sitting at the bottom. “So glad I don’t actually have to go down there,” she said with a shudder, pulling her head out of the shaft and walking around it to turn on the transmitter. As soon as the symbol lit up, Rainbow took to the air and flew to the tower. She landed in front of the control panel and looked it over before pressing the button for the water transmitter. The glass screen flashed and then displayed an image of the stone enclosure around the lava vent, with some of the trees from the grove visible behind it while hissing static came from the speakers. Frowning slightly, she pressed each of the other yellow buttons in turn, granting her four other views of spots around the lakeshore. “Well, that’s helpful,” Rainbow said snarkily. She switched back to the water symbol and then pressed the right-pointing green button. The image began to scroll to the right, and Rainbow glanced up to see one of the dishes rotating around the tower. Looking back down at the screen, she saw the transmitter tower in the trees come into view and released the button. The triangle began to flash slowly as the sound of trickling water became audible through the static. Dash adjusted the image until the transmitter dish was in the center and gave a triumphant smile when the static vanished, leaving only the clear sound of flowing water coming from the speakers. She then worked her way across the board, setting the dishes for the rumbling lava, the broken clock, the musical crystals, and finally the wind from the tunnel into place so she could clearly hear each sound. Satisfied, Rainbow looked at the maroon button and asked, “Now, what do you do?” as she pressed it. The image cycled through the five channels, starting with the lava, followed by the wind, the clock, the crystals, and finally the water. I take it this is supposed to be the key, she thought, pressing the button again. The images and sounds cycled in the same sequence, so Rainbow ran it a few more times to commit it to her memory. Once she was sure of the pattern, she turned to leave, but then paused and took a moment to close the doors on the control panel. Using the clock as her landmark again, she flew back to the mainland and then walked around to the building in the hillside.
“Ok, let’s see here,” the pegasus said, stopping in front of the panel with the sliders, “Rumbling sound first…” For whatever, reason, the sliders were less appropriate for non-magical manipulation than the ones inside the rocket on Aitran, so Dash had to alternate between moving them and pressing on them to listen to the sound they made at each point. Luckily, there weren’t nearly as many possibilities as there had been in the rocket, and each slider had the same collection of sounds, so it only took a few minutes to position all five properly. Dash pressed the button underneath the panel’s speaker and sat back while the sliders sounded off in sequence. She cheered as the button lit up green and the door slid out of the way. Her excitement dwindled as she looked inside and saw a staircase leading deep underground. The walls and ceiling were made of metal and illumination was provided by lights embedded in the walls ever few feet, giving the place an industrial atmosphere. Rainbow took a breath and looked around, trying to decide if she had other options. “I need to find a way out of this place,” she said, “and… dang it, I’ve been everywhere except whatever lets grounded ponies get to the big tower.” She looked back into the building and told herself, “You can do this Rainbow. It’s obvious that ponies are meant to go in here, and it looks sound. So far anyway…” Forcing back her claustrophobia, the pegasus stepped through the doorway and started down the stairs. The décor remained consistent the entire way, maintaining the image that the place had been built for a definite purpose and that the designer did not wish to remind occupants that they were underground. At the foot of the stairs the passageway turned to the right and led to a door with a glowing button in the center. The sight actually made Rainbow relax a little, reminding her of the living quarters on Aitran, which had been surprisingly comfortable thanks to the illusion windows. Latching on to the distant hope of finding something similar, she galloped down the hall and pressed the button. Her hopes were dashed as the door slid open to reveal a wide circular cavern. A metal walkway went around the circumference of the cavern, which was dominated by a large metal object hanging over a deep pit from a piston on the ceiling. A set of stairs led up to a hatch on the side, and as she walked around it Rainbow saw a window on one end, clear evidence that it was a vehicle. Finding nothing else in the room, Rainbow stuck her head over the railing and peered down into the deep, dark pit below. Floodlights at the bottom showed a kind of rail track and Rainbow realized with horror that she was expected to head down there to continue her search for an exit. “No,” she said, backing away from the edge, “No. Way. That’s too deep. It’s… it’s in that other tunnel! It has to be!” She bolted out the door, up the stairs to the surface, and then flew as fast as she could for the radio tower. She landed on the winch lift in the tunnel access shaft and started to operate the winch, only to stop after a couple seconds. “Wait a second,” she said, miffed at herself, “I’m sending myself into an underground cave to avoid going into a bigger underground cave. What is wrong with me?” She dropped to her stomach and rubbed her temples, trying to calm her mind and think straight. “Even if Twilight can get into the rocket and get to me, I’ll have to go through that cave to get out of this place,” she reasoned, and then stood up with determination. “I have done the impossible,” she said, “I have pulled off a Sonic Rainboom. Twice. No stupid, deep, far-from-the-sky cave is going to beat me.” She gulped and spread her wings. “I’ll just have to do it as quickly as possible.”