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// The Solitaire 
// Story: Book 1 - The Behemoth came to Canterlot 
// by Equimorto 
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It all started with a letter. Twilight found it on her desk one afternoon, after coming back to her study. At first she didn't notice it, but once che actually sat down her eyes fell on the grey envelope there in the corner. She picked it up, assuming it had been left for her while she was away, and opened it.
The sheet of parchment she pulled out was blank. She frowned, turning it around in her magic to make sure it actually was, and she hadn't just been staring at the wrong side. She was about to switch to revealing spells to check for hidden messages, when the itching in her horn told her that something was happening with the scroll. She set it down just in time to see words appear on the surface.
Princess Twilight Sparkle, I presume?
A spell similar to the one she used to communicate with Sunset, mostly likely combined with a trigger when the envelope was opened to warn the one on the other side. That was ingenious, and a good way to communicate without risking someone intercepting the letter itself, assuming some sort of password was established between the ones meaning to use it. She needed to study the scroll, the spell could turn out useful in the future.
Putting those thoughts aside, she picked up a quil and wrote her answer. She did wonder who it was on the other side though. A few moments later, more words began to appear on the parchment.
Check behind the desk, on the wall, near the ground.
Twilight paused for a moment, staring at the letter. She got up, pushed her desk away from the wall just enough to slide behind it, and looked down. There, cut into the wall, was a rectangular hole not much deeper than a hoof. And inside it something, wrapped around in a grey cloth. She carefully took it out, but didn't check the contents immediately, instead going back to the letter.
Who are you?
The answer didn't take long to arrive.
Not anyone you would know.
Twilight's breathing was just a bit faster, less steady. They'd reinforced security after the incident, specifically to avoid someone sneaking in again. She unwrapped the cloth. Inside was a glass box, and inside the box what looked like the feather of a very large animal. But its off-white, reflective colour was all too familiar to Twilight, and the way it seemed to shine a light of its own sent a shiver down her spine. She set the box down on her desk and covered it with the cloth.
What is this?
She waited for the answer, breath shaking. Again, it didn't take long.
Your world is in danger, more than you realise. I want to talk. I'll contact you three days from now, in the laboratory.
Twilight stared at the letter. After a moment, more words appeared.
Treat the feather like you would a scale. The spell should be stable enough for it too. See where it takes you.