“My dearest Sombra, one of these days you’re going to be a great leader for our people.”
 
I used one of my own bases lol  
Poor guy was just going to start growing taller like his mom right before the incident lol.
 
This is a design for Sombra based on the headcanon I wrote about him being a corrupted Kirin, and the son of the leader Rain Shine. I’m going to copy what I wrote for him down here:
 
A long time ago, Sombra was born in the Peaks of Peril like every other Kirin.  
He lived the same ways as they did. Honestly and kindly. He loved nature and the outdoors, and was a huge fan of musical theater in his youth, though even if he was reformed he’d never admit that.
 
Sombra, the happy-go-lucky son of the leader Rain Shine, was one of the cutest colts you’d ever lay your eyes on. He was singing and humming practically all the time, bouncing around everywhere, went exploring often (To his mom’s dismay sometimes, he’d get himself into danger), and was overall just a bundle of joy to be around. He was the apple of his mother’s eye, and he couldn’t wait to be the new leader of the Kirin!… Or at least, lead with his mother. It didn’t matter to him too much though, he loved his mother just as much as she did him.
 
Then the Kirin were attacked.
 
They did their best to defend their village, and for the most part, nothing of importance was destroyed. However, Sombra had completely lost his horn in the attack.
 
This was something the Kirin had never seen or experienced before. They and Rain Shine did their best to help Sombra, trying to find cones or other tree branches or ANYTHING to replace his horn. They couldn’t find any way to get them to stay on for more than maybe a few hours (and this was typically forcing it to stay on there), and even then he couldn’t use magic. All his magic was in the horn that fell off.
 
 
This depressed him greatly. He took is broken horn and went into hiding in his home, making a necklace out of it. He wept, watching as his Kirin traits started to disappear. His scales started to die, darken flake and fall off. The long tail he had receded to just the hair. The plate on his head was starting to wiggle and fall off a bit when he decided on his own to leave the village and try to live elsewhere. With no horn or magic and loosing most of his Kirin Traits, he felt alienated from the Kirins despite them trying to make him as comfortable as possible and needed to leave immediately. When he left, he left his mother a note and gave her a kiss in her sleep, which briefly woke her up, but not enough to know what was happening. She was heartbroken the next day. The Kirin kinda lead themselves for bit so she wouldn’t have to worry and could just grieve.
 
He found a place elsewhere in the forest where he he was alone. No other creature was seen for miles. He lived there for months, scavenging for berries and other food to eat. Only one of the scales on his headpiece fell off.
 
Then, seemingly out of nowhere, a mysterious shadowy mist approached him, claiming it could give Sombra his horn back. Though he was weary at first, the shadow convinced him he could help. However, Sombra didn’t know this would mean the shadow would possess him and become one with him.  
He only stayed at the makeshift home he had for a few days longer before heading out to the Crystal Empire where he would reside.
 
Soon, the sweet, kind Kirin Princess Amore and the others met was lost and corrupted, completely merging his personality with the shadow. His powers changed his colors to coal black and a darker grey.  
She called him Sombra because of it, as she reminded him of the darkness of shadows. (Playing on the nature theme of the Kirin’s names.) This was a very sad coincidence.  
The darkness’s power was different than the power of the Kirin, so even though he had magic, it didn’t fix/restore the Kirin traits that had disappeared from him.