I Dream of Haven (DREAM GHOSTS ARE REAL!)
Author's Note
The murderous noble in "Hamlet" is named Claudius...but I have to ponyize his name, right? 
I Dream of Haven (DREAM GHOSTS ARE REAL!)
In Pipp's dream, she stood atop the highest tower of Zephyr Heights, upon an observation deck.
Beside the pegasus filly, her mother materialized: Queen Haven.
Haven said, "Hello, dear. I have a lot to tell you, so pay attention this time."
Haven took a deep breath. "Two days after he married me, Duke Clopius had my royal appearance's flight-faking wires sabotaged. That's how I fell on my head and died in front of thousands of our loyal pegasus subjects. THAT'S how he became regent and guardian over my poor little ponies. He and his son Hayertes have been secretly plotting to marry Hayertes to your big sister, the heir to the throne, so Clopius and Hayertes can rule Zephyr Heights forever."
Pipp shouted, "You think I don't KNOW this? That's what you told me LAST night, and the night BEFORE! And their plot to make Zipp marry Hayertes isn't exactly a SECRET! Clopius has been dropping hints about it for the last three months. 'Just to assure your future,' he says. Those two are real creeps."
"Well, then." Haven nodded. "I'm glad you remember. So why haven't you and Zipp avenged my death yet?"
"Zipp and I are just two fillies. What am I supposed to do, tell the royal guards I had a bad dream, so they should execute Clopius? If I tried that...they would say I must have eaten some bad pizza. They might even accuse me of putting ANCHOVIES on it. Everypony knows that's one reason earth ponies are so bad, because they smuggle the anchovies into Zephyria that BAD FOALS take to get high and hallucinate." She shook her head. "So what do you expect me to do?"
Haven smiled. "So you DO want to avenge my death?"
"Trust me. If I have to hear Clopius and Hayertes ask ONE MORE TIME whether as 'the runt of the litter' I'd rather marry Hayertes along with Zipp, or 'accept Clopius' gracious offer' to marry me himself..."
Haven frowned. "How disgusting. It's time I told you the next step to getting our revenge."
"Even if it means feeding both Clopius and Hayertes into a wood chipper, I'm all for it. I hate those two SO MUCH."
Haven leaned in close to her youngest daughter. "Listen closely..." she whispered.
***
The next evening, Pipp pulled Zipp aside. "Hay! Big sis! I want to talk to you, Pipp-to-Zipp."
"Sure," Zipp agreed. "What about?"
"Come with me into the Palace gardens...where there aren't any curtains for eavesdroppers to hide behind."
Zipp led her sister into a hedge maze. "Now that we're alone...last night I had a dream."
"So? Ponies have dreams every night."
"But this was the SAME dream as I had the night before, and the night before that. That means...this must be a SPECIAL dream."
Zipp snorted. "Was it the dream about three underwear catalog models and a gallon of preening oil, again?"
"No! This was a dream about our mother. She...gave me some very specific instructions, for both of us to follow."
Zipp shook her head. "Our mother is dead, Pipp. We have to accept that."
Pipp thought for a moment. "I never thought YOU of all ponies would be afraid."
"What? I'm NEVER afraid. I just...don't believe in ghosts, that's all. Dreams aren't real, and dream ghosts are even LESS real."
"If you aren't afraid, you wouldn't be afraid to go to the Palace library at midnight tonight with me, would you? Of COURSE you wouldn't be afraid. Unless you're a scaredy-foal."
Zipp stomped a hoof. "I'm not a coward. And ghosts aren't real. But I'll come along with you anyway, just to help keep you out of trouble."
"Thank you so much!" Pipp hugged her sister, and kissed her on the cheek. "The dream said it was important you come along. Thank you. You're the BEST sister ever."
"Yeah, yeah. Now we'd better run along to dinner, before anypony wonders where we are."
***
Late that night, Zipp nudged her sister. "Hay, you little fluffwings. It's time to sneak out to the library."
Pipp's eyes opened. "You remembered."
"How could I forget?" Zipp snorted. "Besides, if we don't go...you'd probably never let me hear the end of it. And I AM a little bit curious."
Pipp opened a window. The two pegasus fillies climbed out into the vines growing on the palace walls, which they used to evade the first set of nighttime guards.
By sneaking carefully through the Palace and its grounds, the fillies entered the Royal Library.
"I don't see what's supposed to be so special about this place," Zipp grumbled. "Just a bunch of dusty old books."
"Not just ANY bunch of dusty old books," Pipp said. "You remember the legend of Bloody Mary?"
Zipp laughed. "We tried that one years ago. And as you might remember, nothing happened."
"Yes," Pipp said. "But...the instructions Mother gave me are special. And this library is a special place. And midnight in a library is a special time, too. Now we just need a big, thick book."
Zipp tapped an unabridged dictionary on a stand. "Will this do?"
"Yes! That's perfect!" Pipp reached with one forehoof. "Let's both of us open it at the same time, to...somewhere in the middle."
The two fillies opened the book, together.
"And now...say the name along with me. Three times."
Zipp snorted, but nodded.
"Twilight Sparkle, Twilight Sparkle, Twilight Sparkle."
The two fillies stared at the book's pages, finding...nothing more than a dictionary's usual innards. They looked around for...any sign at all.
A minute later, Pipp sighed. "I should have known it was too good to be true."
"No," Zipp said. "I think we might have been a minute early. Do we need to say it at midnight EXACTLY? Let's try it again.
"Twilight Sparkle, Twilight Sparkle, Twilight Sparkle."
Again, the fillies searched for any sign, any manifestation of magic at all.
Pipp sighed again. "Maybe somepony slipped anchovies into my dinner...three nights in a row. After what they did to Mother..."
Behind the fillies, somecreature cleared her throat. "What did they do to your mother?"
"AAAA!" Pipp screamed, while Zipp leaped into the air and landed in a karate stance. "Who are you?" Zipp shouted.
A wavering, blurry purple figure chuckled. "You should know. You called me by name, and I came. I was afraid everypony had forgotten me. How did you find out?"
Pipp said, "My mother told me, in a dream. She's dead. Duke Clopius had her murdered."
Twilight winced. "That...sounds horrible. I'm sorry, little fillies."
Zipp grimaced. "Don't call me little!"
Twilight might have smiled slightly, for a moment. "Ok, two mostly grown up fillies. Young mares. But either way...no matter how young or how old you are, having your mother murdered is a terrible thing. I offer my condolences and sympathies."
"Thank you," Pipp said, and Zipp echoed.
"Now..." Twilight took a deep breath, or appeared to. "Why have you called for me? Are you having trouble finding a book?"
Pipp grinned, showing her teeth. "You might say that. My mother told me you could show us the way to the Alchemical Almaghest."
Twilight's eyes narrowed. "The Almaghest? That's some pretty serious stuff. It's very dangerous."
"And letting a murderer like Clopius rule Zephyria ISN'T dangerous?" Zipp stomped a hoof. "I'm willing to take any risk to defeat him."
"Well, then." Twilight pursed her lips. "I have to ask you two to be careful. The Almaghest is dangerous, even deadly."
"Good!" Pipp's eyes flashed with anger.
"Dangerous and deadly not only to this Duke Clopius, but also to any pony who tries to wield the book's powers. Make one mistake, one false move, and you could lose life and limb. BOTH of you could join your mother, in an instant."
"With Clopius on the throne, life isn't worth living." Pipp growled.
"And I would give my own life to protect my sister, if that's what it takes!" Zipp added.
Twilight sighed. "I just hope this turns out better for you two than it did for the last pony who tried to use the Almaghest's treacherous magic." She sighed again. "Centuries ago, Zephyr Breeze hoped to win the heart of his sister's best friend...but he made a serious misjudgment, and destroyed Equestria, fracturing its remnants into three separate, petty realms."
"Zephyr Breeze?" Pipp asked. "Zephyr...is his name a coincidence, or was our kingdom named after him?"
Twilight shook her head. "I don't like to talk about that. It brings back such terrible memories. Just...take his mistake as a warning."
"Sure," Pipp said. "And now that we've been warned, where's this book?"
Twilight led the two pegasus princesses deep into the Library. She stopped in one aisle. "Now this shelf...only appears between the hours of midnight and one, and can only be seen and touched by ponies whose hearts are pure. Well...relatively pure."
Zipp chuckled. "That's Pipp, all right. She's such an innocent."
"Hay! Like you're such a big deal. Are you saying you're guilty?"
"Now, now." Twilight chided. "I advise you two, whenever you aren't using the book, to put it back on the shelf. Really, you should ALWAYS put the book back before the hour of one, so ponies who are less pure hearted than yourselves won't find the book and misuse it in some horrible way that could cause a huge disaster."
"Sure," Pipp said. "Now where's the book? Is it THIS one?" She pulled a book from the shelf, and opened it. "Alchemical Almaghest: Ye Alchemy Av' All Elements, First Edition."
Twilight nodded. "Be careful to heed my warnings. Never misuse the book, always respect its dangers, and always put it back on its shelf before one o'clock of the night, to help protect the tome from unworthy eyes and hooves. Also..."
"Also what?" Zipp asked.
"I wish you two the best of luck." The purple specter vanished.
"Ok," Zipp said. "I guess I DO believe in ghosts. And in dream ghosts, too. Because I don't know any other way to explain what just happened."
Pipp barely heard, with her eyes already fixed upon the book's first page.
