Books and Branches Library, Ponyville

"Is it time yet?"

Twilight Sparkle looked up at the clock, watching the second hand approach the twelve o'clock position in perfectly timed increments. "Almost," she said as she took up her position by the window. Spike stood by the main entrance to the library, hand poised to unlock the door at the unicorn's signal. They weren't normally so concerned about opening the library on time, but today was the day of the new book delivery and the librarians wanted to be ready the moment Derpy arrived with the box. The grey pegasus had impacted the door once when Twilight had been a little late in unlocking it, and the poor things was dizzy enough as it was normally without repeated head trauma like that. Twilight gripped the "Open" sign in her mouth in preparation for hanging it in… t-minus ten seconds, and then glanced outside and dropped it. "Spike," she said warningly, "you might want to move so you're not behind the door when you unlock it."

"Why?" the baby dragon asked, "is Derpy coming in too fast?"

"They're coming fast," Twilight said, "but it's not Derpy." Spike shifted to the side as Twilight shot one last look at the clock, and then out the window, and called, "Go!" She lifted and hung the sign with her magic as Spike undid the lock just in time for the door to be flung open to admit a cyan blur with a rainbow highlight. It came to a sudden stop just short of the table in the middle of the room and, once the dust settled, became recognizable as Rainbow Dash.

"Is it here yet?" she asked bouncing slightly as she grinned hopefully at Twilight.

The lavender unicorn had a pretty good idea about what her friend meant, but she decided to ask anyway, "Is what here yet?"

"What do you think?" Rainbow retorted, "What could possibly have me rushing over here, on purpose, on new book day? It is new book day, right?"

"It is," Twilight said, glancing out the window as she smiled, "but you beat the delivery by a good margin."

"Oh," Rainbow said with a sheepish smile, "I… guess I'm just that good then, aren't I?"

"Whatever," Spike said, rolling his eyes. He started to walk away from the door, only to be bowled over by a box as big as he was that came swooping in for a stop in the grip of a grey-coated pegasus with off-kilter yellow eyes.

"Special derp-livery," the unflappable Derpy said as she set the box down and landed on top of it. Seemingly oblivious to Spike, who was rubbing his head and glaring as Twilight helped him to his feet, she gave Rainbow a bright smile and a wave. "Good morning Rainbow Dash!" she said.

"Hello Derpy," Rainbow replied automatically. Derpy's smile somehow got bigger and she gave Twilight a nod before hopping off the box and leaving. "I'm never sure where that pony's mind is," the cyan pegasus said as Twilight closed the door, "Or what she's looking at."

"Definitely not where she's going," Spike muttered darkly, still rubbing his head as he headed toward the kitchen, "I think I need an ice pack Twi. Be back in a second."

"Go ahead and take a break Spike," Twilight said with concern, "I can sort these books out on my own." She picked the box up in the magic and carried it toward the back of the room, noting with amusement that Rainbow had moved quickly to look over her shoulder. "Patience Rainbow Dash," she chided gently, opening the box, "I'm sure it's in here. You'll just have to wait for me to get it out." She carefully removed the tape holding the box closed, opened it up, and lifted out a book. "Devilish Delights," she read, "A guide to maximizing your per-bite chocolate intake. Pinkie Pie would probably enjoy this." She it aside and pulled out the next book. "Dashing Debonair Designs for Delightful Dressage Demonstrations. Sounds like something I should recommend to Rarity." Another book floated out of the box. "Oh, I've been waiting for this one," Twilight said.

"What?" Rainbow said, getting exasperated with the wait.

"The first authorized account of our battle with Discord," Twilight explained, floating the book over to the uninterested pegasus, "written with comparisons to the old legends and myths regarding him."

"Ok, kinda cool, but I don't care," Dash said, pushing the book aside.

"Ok, ok," Twilight said with amusement as she sent the book toward a shelf and looked into the box again. "Ah, here we go," she said, levitating out a mustard-colored book with a colorful and easily recognizable picture printed on the front, "Daring Do and the Huaca of Huetotl."

"Awesome!" Rainbow declared, grabbing the book and hugging it to her chest, "I can't wait to start reading."

"Is that the new Daring Do book?" Spike said from the kitchen door. He was holding a small ice pack to the back of his head and he came over and gave Twilight a disappointed look. "I thought I was going to get the first shot at it," he said.

"Sorry Spike," Twilight said, showing the baby dragon a list she grabbed from the table, "but Rainbow put her name on the reservation list."

"I know," Spike said with a sigh, "I just wasn't expecting her to get here so early."

Rainbow laughed at Spike's disgruntled look and took a seat on the stairs. "Sorry kid," she said, "No pony and no dragon beats Rainbow Dash to her favorite books."

"Just don't spoil anyth- urp." Spike's cheeks bulged as he turned away and belched up a tongue of green fire that quickly transformed into a scroll. Twilight looked up from her sorting and was about to comment when Spike burped again and another, larger scroll materialized.

"Two letters? That's unusual," Twilight noted as Spike grabbed both and looked them over.

"This one says to read it first," Spike said, setting the second scroll aside and unrolling the first. He cleared his throat and began reading in an officious manner, "Dear Twilight Sparkle, I am forwarding a letter meant for you and Rainbow Dash. Our mutual friend Star Swirl the Bearded," Spike's voice slowed down and he raised an eyebrow slightly as he read the name, "appeared in the throne room just minutes ago and requested that I send it. He said it was of the utmost importance that you respond quickly, and after reviewing his letter I must agree. Star Swirl has already returned to Aitran and awaits you there. Signed, Princess Celestia."

"Star Swirl," Twilight said quietly, picking up the second scroll in her magic.

"I'd almost forgotten about that guy," Rainbow said, setting Daring Do aside and standing up, "How long ago did we stumble into Aitran? Three months?"

"More or less," Twilight said, opening the letter, "I wonder how long it's been for him? Well anyway, here's what he wrote:"

My friends Twilight and Rainbow,

I write to you on a matter of great importance which I hope you will be willing and able to assist me with. You may recall that shortly after we met I determined that my wife and daughter were trapped in another world known as Sohndar. Since we parted ways I have devoted my time and effort to verifying this fact and attempting to stabilize the link to Sohndar. My greatest hope and fears have both been confirmed: Clover lives, but she is in the custody of the enemy she and I struggled to isolate in that world so long ago. I know not if Nyx is with her as well.

As I am asking for your help, I know you will want some more information about the situation, and by learning it you will be better able to make your decision. Sohndar is not a world I personally discovered, but it is one that I am quite familiar with. It was originally linked to by the one I have simply referred to as my enemy up to this point. His name is Aldro, a being who greatly resembles a race of cave-dwelling Equestrian creatures known as Canis Anancite."

"Say what?" Rainbow asked, confused.

"Diamond Dog," Twilight translated, quirking an eyebrow in surprise. She resumed reading while Rainbow muddled over that bit of info.

"We were not antagonists at first. We crossed paths early in my career as a traveler between worlds, and he helped me come to a better understanding of the basics behind Writing. Aldro claimed to be the survivor of a civilization that had raised World-Writing to an art form, only to collapse due to a sudden plague coupled with disaffected citizens undermining their culture. I don't know how much of that tale is true, but if Aldro is an accurate representation of his species, it's probably for the best that they have fallen. He firmly believes that by Writing the linking books, he and all others who possess the skill actually create the worlds the books link to. Such an attitude gives him something of a god complex in regards to the inhabitants of the places he's discovered. He does not even deign to name "his" worlds; in his records, Sohndar is simply "The Fifth Age." His skill in Writing is… debatable to put it mildly; every world he's linked to in his life, or those I've seen at least, has some fundamental instability that his linking seems to aggravate, leading to their eventually collapse and death. Sohndar is probably the most stable of Aldro's collection, but even it is breaking apart.

It's also Clover's home world. She and I met on my first visit to Sohndar, and I took her away at her request. We chose to trap Aldro there because we were sure that once we had destroyed all of the linking book in that world, he would not have the means to construct a new one from the local materials.

I'll tell you more when you arrive. For now I must return to my writing.

I hope to see you both soon.

Star Swirl.

Twilight rolled the letter up and looked at Rainbow, head cocked to the side in inquiry.

"What does he need us for?" the pegasus asked, "It sounds to me like he's got all the answers already."

"We won't know until we go," Twilight said, setting the scroll down on the table and heading toward the stairs, "I get the feeling we might be gone for a little while though. I'm going to bring some stuff just in case. Would you mind telling the girls so they don't worry?"

"Sure thing," Rainbow said, unfurling her wings as she started toward the door. She paused after a few steps and looked back toward Twilight, asking, "If any of them want to come with us, what should we do?"

Twilight thought about it for a moment and then said, "I'd be quite happy to have anypony who wants join us. The more minds and viewpoints we have, the better, right?"

Princess Celestia's Chambers, Canterlot

"Absolutely not," Princess Celestia said, placing a hoof firmly on the copy of Aitran, "I am sorry Twilight, but I share your feeling that Star Swirl will be asking you and Rainbow Dash to enter this land of Sohndar. It is difficult enough to send you into a place beyond my ability to come to your aid; I will not risk losing all six of the Elements of Harmony in one fell swoop."

"Aww," Pinkie Pie said, sounding like she'd just been denied candy.

"I reckon you're right Princess," Applejack said, "but it don't feel right not being able ta support them…"

"Ah, don't worry AJ," Rainbow said confidently, "Twilight and I handled everything Star Swirl's books threw at us. I'm sure this'll be a piece of cake."

"Thank you all for volunteering to come with us," Twilight said, smiling at her four other friends, "Especially you Fluttershy." The yellow pegasus kicked at the floor meekly, and then surprised everypony by jumping forward and hugging Twilight.

"Just come back please," she whispered, and then hugged Rainbow and said, "you too Rainbow Dash."

"No worries 'Shy," the cyan pegasus said, patting Fluttershy's back, "We'll be back before you know it. Pinkie Pie Swear." The eponymous pony gave Dash an expectant look. "Cross my heart and hope to fly," Rainbow began to recite, making the motions.

"Stick a cupcake in my eye," Twilight joined in, remembering to close her eye before poking it with her hoof.

Celestia allowed the six ponies another moment as they came together for one last group hug and then coughed clearly but politely for attention. "Are you ready, my little ponies?" she asked.

Twilight and Rainbow reluctantly separated from their friends and nodded as one. "Yes Princess," Twilight said, "as ready as we'll ever be." Celestia nodded and lifted her hoof from the book, sliding it toward the waiting pair as she magicked it open to the final page, where the magical linking panel waited to transport any who touched it to the dock of Aitran Island.

Library, Aitran

In many ways, the most important building on the entirety of the small isolated island of Aitran was unchanged. It was still a cubical marble structure built in the Classical style slightly into the base of a steep mountain, the interior was still a single wood-paneled octagonal room, and the three-shelf bookcase and paintings were still in their places. In other ways, however, it was quite different. The bookcase was almost empty save for five books, the ashen remains of the former occupants having been cleaned out. Two alcoves on the north and south walls, which had once held the paper-and-ink prisons of Star Swirl's rebellious apprentices Cirrus and Archeon, were also empty. In the center of the room stood an octagonal wooden pillar with a niche in one side holding the pearly-white linking book that led to the throne room of Canterlot Castle in Equestria. On top of the book sat a note written in Star Swirl's script:

Friends, I am waiting for you in my private study. If you've forgotten the fireplace code, I've drawn it out for you on the back of this note. Theoretically, two ponies of your size could fit inside the fireplace at the same time, but if that doesn't appeal to you, at least leave the green book somewhere easy to find that's not on the floor.

"Go to it egghead," Rainbow said, giving Twilight a nudge toward the green-brick fireplace, "I'll be here."

"I would hope so," Twilight responded, taking the note in her magic and crawling into the fireplace. She activated the code panel, copied the pattern of squares from the note on to it, hit the switch and waited for the room to rotate, and then plucked the green book from its hidden shelf and spun the fireplace back around. She crawled out of the fireplace, walked over to the neighboring alcove, set the book in it, and then opened it to the final page as Rainbow came over to join her. "We're here Star Swirl," she announced to the grey-bearded unicorn visible through the panel before touching it and letting the book transport her. Rainbow was only a second behind her.

Star Swirl's private study was an underground cavern, with the only entrances and exits being linking books. The ancient unicorn scholar himself was standing behind a desk on a raised portion of the floor, concentrating fully on writing in a thick tome. The quill paused as Star Swirl glanced up at the two mares, and then he looked back down, continuing to write as he spoke, "Thank you for coming my friends. As you may have surmised, the favor I must ask is that the two of you go into Sohndar, rescue Clover, and find out what you can about Nyx's fate."

"Why can't you just go yourself?" Rainbow asked, suspicious.

"There are two reasons," the old unicorn answered, "Aldro has undoubtedly kept Clover alive to lure me into going after her. He won't be expecting other visitors. Secondly, I must stay here and try to keep Sohndar stable while you work. Here." He horn flared a little brighter and a small book floated off the desk and toward Twilight. "This is a journal of my recent work; it should explain things a little better. Keep it safe. Also," he looked up and pointed with a hoof to one side of the room, "I believe it would be best if you go in disguise."

Twilight and Rainbow followed Star Swirl's hoof and saw a pair of roughly woven brown hooded cloaks, designed to cover as much as possible without restricting movement. They went over to the cloaks and Twilight picked them up in her magic to get a better look. "Uh, Star Swirl," Rainbow said, "neither of these have holes for my wings. How am I supposed to fly in this?"

"You're not," Star Swirl said simply, focused back on his book, "There are no pegasus ponies in Sohndar, only unicorns and terr- er, earth ponies. You must try to avoid drawing too much attention to yourselves; Aldro will not be kind if he learns of your intentions and manages to capture you."

Rainbow glowered at the cloaks and said, "I'm having second thoughts about this. What good am I if I can't fly? Twilight's got all the smarts you'll need."

"I'm not going to do this alone Rainbow," Twilight said, "You might notice things that I don't, we can keep each other grounded, and… Er…" Rainbow glared at her and she blushed in embarrassment. "Sorry…"

"Well, I guess moral support's a good enough reason," Dash said resignedly, "Gimme the cloak." Twilight settled the rough garment over her friend and then put her own on after removing her saddlebags, putting them back on over the cloak, and then the two walked back to Star Swirl's desk, Rainbow's wings twitching uncomfortably in their confinement.

"Thank you both," the bearded unicorn said, glancing up briefly, "One last thing before I send you in." His horn flared again and another book floated toward Twilight. "For reasons of safety, I can't send you with a direct way back, but I can give you this: this is a trap book that appears to link to Aitran."

"Hold on," Twilight said, pushing her magic against the book to stop its movement, "how are we supposed to get back if we don't have a working linking book? And why send us with a trapped book?"

"If Aldro discovers how you reached Sohndar, he'll expect you to have a way out," Star Swirl explained, "You'll probably need to capture him in this book in order to reach Clover and escape safely anyway. In fact, I want you to trap him. After you've accomplished everything, find a way to signal me and I'll come with a linking book." He wrote a little bit more in the book, looked the page over, and then closed it, picked it up in his magic, and opened it to the first page, which had a linking panel on it. The image was fuzzy and jittery, preventing anyone from getting a clear view of what lay within.

"Are you sure it's ok to use?" Twilight asked, looking askance at Star Swirl.

"The link is stable, I assure you," Star Swirl said.

"Well, ok then…" Twilight put the trap book in her saddlebags and then hesitantly lifted a hoof and reached out to touch the unstable image. The world faded away around her and for a few tense seconds all she could see was black. Then the light returned, the floor sank slightly under her feet, and bars sprang up in front of her, trapping her within a round metal booth.