Since she saw that crystalline velvet of the cover of the book The Most Mysterious Places, Rarity didn't stop thinking about certain creatures mentioned by Cadance. What she wouldn't give for finding the crystal butterflies and use the silk from their crystalline cocoons to create her dresses. However, the crystal butterflies were gone, having fled from the Crystal Empire when the King Sombra came to power. Anypony hadn’t seen them since that day.
But Rarity wanted to change that. She wanted to find the crystal butterflies and make them return to the Crystal Empire, not only because it was the right thing to do, but also because she wanted so much that silk of theirs, so she could use it to create things as beautiful as the velvet.
Of course she couldn't do the job alone. She would need help. First, She had to find the butterflies and then she would have to convince them to return. But how could she do that?
To find them, she asked for help to Twilight. After all, she was an expert at this sort of things. Then, to convince them, she decided to ask for help to the greatest animal expert she knew: Fluttershy. She was sure that she would accept. After all, they were a new type of animals, butterflies, one of her favorite animals.
After having left Twilight’s library after she had given her what she thought was the location of the crystal butterflies, taking into account the type of environment and conditions that they liked and the description of their migrations, Rarity went to Fluttershy’s cottage, bringing her saddlebags. She knocked the door, calling her:
"Fluttershy, my dear?"
The door opened and Fluttershy appeared, saying:
"Oh, hello, Rarity" Fluttershy greeted. "What brings you here?"
"I came to invite you to a small incursion I'm planning" Rarity replied. "Do you want to come?"
"I don't know, Rarity" Fluttershy replied. "You know I'm not much for incursions."
"But I think you might want to come on this" said Rarity. "You know, I'll try to find the crystal butterflies."
"The crystal butterflies?" Fluttershy asked, getting excited. "Oh, I've heard about them, but nopony had seen them for a thousand of years."
"Yes, since King Sombra appeared in the Crystal Empire" Rarity said, using her magic to take from her saddlebags what appeared to be a map. "But Twilight was able to locate their possible whereabouts. It’s a chance in a million, but I think it's worth..."
But she didn't have time to finish because Fluttershy disappeared for a moment and returned with their saddlebags ready and asked:
"When do we leave?"
"Well, you're really excited" Rarity commented.
"This is my chance to search and maybe find one of the most mysterious, fascinating and beautiful animals ever! Of course I'm excited! Why wouldn't I be?"
"Well, rightly so, we've got a long way to go. I'm glad I used my stronger and lasting hoof varnish. We'd better go to the train station to catch the next train."
They went to the train station. Upon arrival to the train station, while waiting for the train, Rarity began to see the map that Twilight had given her.
"So, where are we going?" Fluttershy asked.
"We will catch the train to Tall Tale and then we will go to the Smokey Mountain" Rarity replied.
Upon hearing that, Fluttershy froze.
"Smokey Mountain?" she asked, afraid.
"Yes" Rarity replied. "Apparently, that mountain, as well as the surrounding area, has the cool climate and the discretion that the crystal butterflies love so much. Taking into account that they lived in the Arctic, it’s normal to seek a fresh place to inhabit and how this mountain is constantly covered by mist, is the perfect place for them. I hope you brought scarves. Of course if you didn't bring, I can always borrow one of mines. I have here many scarves."
But Fluttershy didn't say anything, being too nervous. The Smokey Mountain was a place that intimidates her, mainly because the mist, which hid any danger there was out there. But she wished so much to find the crystal butterflies. For that reason, she had to swallow her fear.
The train then arrived and as soon as the doors opened, Rarity entered. Fluttershy still hesitated a bit, but she eventually entered too.