Warning Potential Spoilers
You might think "Oh thats a silly question, Vader." But in reality it's not, what ever happened to his body. His body was full of dark energy. So it could've corrupted the area. Turning it into a dark magic nexus. Or wait could his body exploded after Twilight, was forced to leave. So in a way, this could create millions of story potentials of Dusk what ever his name is. Finding out about his father, and then going ot the castle, and finding a dark magic nexus. Where he finds his father, a dark magic demon/ ghost (your choice). Roaming the halls, tempting him with the powers of the dark magics. So in a way we have a massive dark magic nexus. Which makes no sense because I would expect celestia to destroy. So there you have it, a massive dark magic energy well. Which could actually be where Sombra's soul is trapped forever. And where Sombra can torment anyone that enters.
What is your speculation.

I think that with all the dark magic Sombra had under his knowledge I highly doubt he wouldn't have a backup plan to give himself life once more. Like his horn I would imagine could be storing a fail safe spell to give rise to the great king Sombra once more.

1894029
My view is that he survived but only as a soul stuck in a limbo like state. So he can't get out, he can only torment people/ ponies in a ghost form.

Kufufufufu~ Although he isn't a alicorn, he had the ability to reform from his horn, so as along as his horn or any small piece of his body exists, he could eventually reform. the torment he causes may give more dark energy to speed it up though. But that's my opinion. Kufufufufu~

F1utt3rShI~

(Daemon Spade)

1894046 have to agree with F1utt3rShI on this one my friend.

1894050
A soul isn't a body. It's a living spirit.

1893955

Dusk what ever his name is.

Dusk Trail.

Talking about it like a dark magic nexus makes it sound like a dark side well like on Dagobah. It seems that any place that Sombra could've had influence has potential for this but... True evil never dies,it just waits in any form it can take.
Hasbro pls pay attention to this golden character kthx

Also...thinking about it more and more, should I have used Dusk Trail...? I like it but im feeling conflicted now.

1894406
Exactly. The dark magic well, you see on Dagobah the spirit the resides in the well was suppose to be in the afterlife. SO if this happens to Sombra's body. Then couldn't he indeed take up the form of something people/ ponies fear?