------Shadow's perspective, the week at Crystal Empire------
Shadow reached the Crystal Mine escorted by crystal guards. The crystals were at the bottom of the cave, they looked nothing like anything he ever saw before, they were deep purple with a glistening aura of the same color involving them. "This is nothing like what I saw before, give me some time alone with these crystals, I will start the research right now." Said Shadow.
"Of course Mister Shadow, we will be at the exit of the cave, if there is something you want just shout." Said one of the crystal guard ponies.
"Fine, just bring my things here, let's start with this!" Said Shadow excited.
When Shadow's items arrived he instantly took them and opened the pockets getting plenty of the tools he brought out starting to analyze the strange crystals.
After some time analyzing the crystals the crystal guard ponies came down to check Shadow Walker, he was annoyed that somepony disturbed him. "What is it?".
"Just checking if things are alright down here."
"Things are fine here."
"Good then, we will be back soon."
These crystals are fascinating, they emanate pure magical energy and it's strong.
The first night went normal, he went to sleep and couldn't wait to continue the research at the next day. He spent the night thinking of the strange crystals and their pure magical energy aura.
In the second day, he went to the mine and analyzed the aura once more. Nothing strange, the only thing that I can find is a magical aura, nothing strange at the aura at all. So, he went with the analyzes, what he didn't expect was that the crystals were emanating this energy and slowly influenced who was in range. With this, he went to sleep.
In the third day, things were normal, until Shadow went to the mine again. In the mine, the influence of the crystals were stronger than ever. Shadow started having headaches while analyzing them, a voice formed in his head and was starting to control his body, the voice said '...Crystals...', it was his voice, and everything in Shadow's sight went black.
His body started to change, his horn grew and turned to a slightly recurved shape, glowing red, his mane went backwards, from his eyes a purple stream of magic flowed.
------Merely illustrative purposes, by the way, used without permission, if the author wants me to remove it, then I shall. I used it because I liked it very much. ------
With this, Shadow stormed out of the cave and spread chaos around the Crystal Empire, because nopony was match for his abilities, he easily turned everypony at the Crystal Empire in slaves to gather crystals for him. In the past three days from there, the entire Crystal Empire were Shadow's slaves and could do nothing about it.
The week ended and Princess Luna traveled to the Crystal Empire to seek for her coltfriend and worrying for the Crystal Empire too, she feared that something was going on there and she was right.
Interesting, I'm a fan of Sombruna.