Image imported from derpibooru 
Original Description:
 
The aftermath of everything.
 
As I mentioned in the previous, Sombra lost his pony form, as this was the only way he could fully use his powers and save his daughter from Rabia’s influence.
 
Being an umbrum not just something like a form change. For example, for a short period of time, they can be in the sunlight after that however it becomes painful for them. Almost like their bodies are made out of shadows, so they can’t take to much light. And that’s one of many other things.
 
Sombra also feared that his umbrum nature will become stronger as times goes on.
 
Hope wanted to get help from the princesses, maybe they could give Sombra’s pony form back. However, Sombra refused. Even if they could, the only way he managed to save Notche was with his umbrum powers. Nothing stops Rabia to return later. He wanted, he needed to stay more umbrum to protect her.
 
Another way had to be found.
 
He later managed to learn how to use his powers to give his pony from back (after all umbrum magic gave him one when he was a colt) , but he wasn’t powerful enough to give him one for a whole day. He could be pony at day, but he would turn into an umbrum at night. And it was unknown how long he can even do this much. One day may come that he never can be a pony again.
 

 
There’s one more drawing, but that will be about Notche, so Sombra’s story in my AU is closed for now.