Written by RandomString Proofread by Knight of Cerebus

Twilight slowly woke up, taking a while to recognise her surroundings as Luna's bedroom. As Luna was now sleeping at nights and had company that couldn't see in the absolute darkness, she had taken to leaving the darkness off. The room looked less mysterious, now that Twilight had become familiar with it. In fact, it was starting to feel like home.

Sunlight was streaming through the balcony windows, telling Twilight that is was well past dawn. She stretched, yawned, saved and started to think about getting out of bed.

Twilight's musings were interrupted by Luna bursting through the door at great speed, her eyes wide with panic.

"Twilight, I'm glad you're up. Let's go to Ponyville! Right now."

Twilight watched with alarm as Luna frantically threw together saddlebags for Twilight and herself.

"Luna, what's wrong?"

"Oh, nothing, nothing," Luna lied, "I just think we should get a bright and early start to the day."

"The first train for Ponyville doesn't leave for another two hours, I think, so there’s no need to hurry. Time enough for breakfast, maybe?"

"Oh, who wants to be bored waiting in the train station for a train? Let's just fly there. I'll carry you. It'll be romantic."

The moment Twilight scrambled out of the delightfully soft bed, she had her saddlebags dropped on her and clinched tight. She coughed with surprise and then relaxed.

"Fly? You'll pull the chariot? Won't that attract a LOT of attention?"

"Don't worry, Midnight Whispers can fly. I'll pull it as her."

Twilight could hear a noise in the distance which almost sounded like Luna’s name bellowed in the Royal Canterlot Voice.

"Ahehe. I think we're ready. We can have breakfast in Ponyville. Let's go."

The voice sounded again, much closer this time. Twilight could now hear Princess Celestia shouting, "Where is she?" at considerable volume.

Luna seized the moment to teleport Twilight and herself to the chariot bays. Twilight was quickly placed in a chariot and Luna hitched herself in with speed. With barely a run-up, Luna launched herself into the sky and started flying away from Canterlot at terrific speed. Twilight was clutching onto the chariot guard rail with both hooves in a desperate bid to not fall off.

Once they were in the sky, Luna dropped an invisibility illusion on them, turned towards Ponyville and sped up, eating the distance at an incredible rate.

When they were closer to the town, Luna shifted into her Midnight Whispers form. With her smaller wings and less divine physique the chariot slowed, but was still making good time. They would be there in about half an hour, Twilight estimated.

"So, what did you do?" asked Twilight, now that the rush of the wind wasn't deafening.

"Oh, nothing, nothing," replied Luna, "I may have slightly misjudged a prank. It seems I am still a bit rusty."

"Go on..."

"Well, as you may recall, I had declared Prank War with my sister. It's an ancient custom that we use to keep each other on our toes. And to remind her that I'm better than she is.

"I thought it best to take the initiative, and open with a multi-faceted prank to demonstrate my abilities and intimidate Tia into surrendering early. It was a lot of work, and took up a fair amount of my time yesterday."

"Keep going, Luna."

"I knocked the pins from the hinges on the doors to her quarters and replaced them with spell-wrought constructs. They'd behave just like normal hinges, except they wouldn't last very long. I also enchanted one of the floor tiles in the corridor just outside of Tia's chambers. When we have a prank war going she can be very careful in rooms, but sometimes forgets to check corridors.

"So, this morning when Tia left her chambers, her guards closed her chamber doors behind her as usual. Then Tia trod on the enchanted tile, which was enspelled activate when trodden on by an alicorn. Firstly, it unwrought the replacement door hinge pins I had created. Then it sent a gust of wind behind Tia and triggered a multi-sensory illusion. Can I just say that it is really difficult to get a basic floor tile to do all these things on such specific conditions? Very interesting technical problem."

"It sounds it. Normally I would love to talk about it with you, but I think you be leaving out some key details. Princess Celestia wouldn’t be quite so annoyed if her bedroom doors just fell over. She was amazingly patient with me when I accidentally did more to some of the palace doors than just knock them over."

"Well, the illusion may have something to do with it. Visual illusions aren’t much good around Tia ‒ she has to focus in order to see them, which spoils the fun. ‘Hers is the light of truth’ and all that. But she notices sonic and odorous illusions."

"Sonic and odorous?" Twilight hesitated as her mind put the pieces together, "Luna, you didn’t!"

"I thought it would be a great coup. Show the other ponies that even the divine Princess Celestia is a pony."

"Luna! You can’t just make it seem to the royal guards that Princess Celestia farted down her bedchamber doors!"

"It was funny! It would have been funny. She IS a pony. She’s not that special."

"Not that special?! She’s Princess Celestia!"

"Sometimes she’s just a big, annoying, know-it-all unicorn with wings. And I think you love her more than you love me," this last sounded a little petulant.

"What! Luna! How can you say that? I love both of you, in different ways. You can’t compare what I feel for you with what I feel for Princess Celestia."

Luna was silent for a few wingbeats.

"I’m sorry, Twilight. I shouldn’t have said that. Forgive me?”

Twilight couldn’t climb out of the chariot in mid-air to hug Luna, so she settled for lightly embracing her with her aura. Luna nickered with approval.

"I am surprised," Twilight said after a while, "I can understand the princess being annoyed with your prank at first, but it was quite funny and she actually sounded angry. Were there other witnesses than just the guards?"

"Just one, Argent Shield, one of her ladies-in-waiting."

"That doesn’t sound too bad. They won’t gossip about Princess Celestia."

"She was a very close witness. Very close. As in ‘standing right behind her’. She looked rather dazed, afterwards."

All the tension in Twilight was released as she fell about with gales of laughter.

"She went to help Argent Shield and that gave me time to run. Can you see her behind us, by the way?"

Still laughing, Twilight looked behind her, looking for any hint of pursuit, magical or otherwise.

"No, no sign of anypony."

"Oh dear. That isn't good."

"You wanted to be pursued?"

"Well, I hate to admit it, but I was hoping that if she chased us down, she would have to moderate her response somewhat because of your presence. She couldn't, for example, banish me to the moon because it would cause you to fall to your death or get you banished with me, you see?"

"Wait a moment! I'm here as a pony shield? A hostage?"

"Twilight, you're here as a peacemaker! You'll stop her from killing me straight away."

"I can't believe you kidnapped me to be your pony shield..." said Twilight, suppressing a smile.

"Sorry."

"Well, I still can't see any sign of her behind us, and we're nearly there. Maybe she wasn't as annoyed as you think."

"Tia won’t sit idly by. She'll get revenge somehow. We need to maintain our guard."

"What can she do? If she was chasing us, she would have caught up by now. The palace guard can’t match the pace you set. Surely we’re safe until we reach Ponyville."

"Philomena."

"Princess Celestia’s pet phoenix? Really?"

"She can fly faster than me, faster than Tia. Tia can turn her invisible, so we wouldn’t see her coming. As for what she can do when she finds us, do you have any idea what it’s like to be dusted with itching powder when you’re flying at altitude, pulling a chariot? That beast is a menace!"

Despite Luna's worries, the rest of the flight to Ponyville was uneventful. Twilight attracted some attention, arriving as she did in the black, lunar chariot, but the town gossips were reluctant to comment on this for some reason.

The last portion of the flight for Twilight had been dominated with thoughts of Spike. She knew that if he ran into any problems her friends would be sure to help him out, but still she worried. As soon as they touched down in the centre of Ponyville, Twilight hurried to the library, leaving Midnight to park the chariot at the town hall. Spike was delighted when Twilight burst through the door and they rushed to hug each other in the doorway.

"Twilight! You’re back!", the little dragon exclaimed, and then "Eww! You smell!"

"Thanks, Spike," said Twilight, "it’s good to be back. I missed you. And sorry about the smell, we got up and left in a bit of a hurry this morning. I’ll take a shower as soon as I’ve had something to eat — we skipped breakfast too. Did anything happen while I was gone?"

"Um, no. No. No, nothing at all. Very quiet. Peaceful Ponyville, that’s what they should call this place."

Twilight looked at Spike oddly, but chose not to press the matter further. Food was now very high on her list of priorities. Luna landed by her side and they both made a beeline to the kitchen.

"Oh," said Spike, "a scroll from Princess Celestia arrived about half an hour ago. Marked 'private' and for your attention only. It's on your reading desk."

Both Luna and Twilight froze at the mention of Princess Celestia's name. Once in the study, Twilight and Luna inspected the outside of the scroll from all angles, viewed it through mirrors and crystals and debated several minutes before taking a sample of the parchment and putting it through a rigorous array of tests that failed to prove that it was anything other than paper.

"All right. We have inspected this scroll and have concluded that it is, in fact, a scroll."

"Probably a scroll. Tia knows all sorts of tricks. We have not tested to see if it is soaked in a hallucinogen yet, have we?"

"Seriously? Luna, Princess Celestia wouldn’t risk hurting Spike for a prank, would she?"

"Well, no, but she may know of a compound that would be harmless to dragons but potent to magic users. If she thinks that we worked in collusion with the tile prank, she may consider you a valid target."

"Luna, how serious do these prank wars get?"

"They don’t! They’re harmless fun to relieve the tension between us. I— I may be a little out of practice. Tia does not allow a prank to pulled on her without retribution and I am no longer certain what would count as a measured response."

“Luna, Princess Celestia will not have soaked this scroll with a hallucinogen. It might not even be related to your prank. Maybe we forgot something in Canterlot and she’s letting us know. I will read my scroll and then we can eat. I can’t think on an empty stomach anyway."

As a precaution, Luna stood well back as Twilight opened the scroll and started to read. Luna watched with trepidation as Twilight started grinning like a lunatic.

"What? What's on the scroll? Let me see," said Luna.

Twilight shook her head mutely and kept reading intently, grinning all the while. Luna kept trying to look at the contents of the scroll, forcing Twilight to twist and turn to keep it shielded.

Eventually, Twilight teasingly held the scroll behind her, luring Luna into a trap. As Luna reached behind her for the scroll, Twilight dropped the scroll and brought both her fore hooves to bear on tickling Luna just behind her foreleg, with a gentle rubbing motion.

The effect was immediate. Luna collapsed in gales of laughter and tried to push Twilight's hooves away. It was hopeless. As soon as Twilight was driven from one spot, she immediately moved to another where Luna seemed to be equally sensitive.

It took Twilight about twenty minutes to tire of the game and she finally relented. A breathless Luna scrambled up into a sitting position and grabbed the scroll.

"I'm starting to see how it is between you two. You prank her with sophisticated spells and illusions and she prefers to use others to get her revenge."

Luna opened the scroll and saw that it laid out, in detail, all the knowledge Princess Celestia had gathered over centuries of tickle fights with Princess Luna, detailing all her sensitive spots and how best to exploit them.

A laughing Twilight said, "I really must thank her for the information. This is going to be so much fun. You can destroy the scroll if you like, I've memorised the contents."

Luna brought her head to her hooves with a melodramatic sob, crumpling Celestia's revenge between them.