I drew something like this a while ago but it was made out of hand-drawn linework and some of it wasn't too perfect. I redid him and the only major change is his colt look and I kept his grey coat consistent throughout.

For those who don't know, this is my headcanon/theory of how Discord came to be. I feel like there's a reason why his head is that of a horse and I also wondered why Celestia said he "ruled" Equestria at one point and I got to think that maybe he became the pony king before Celestia and Luna did which just recently became a thing in my fanfic "Age of the Alicorns: Chaos Rising" where Celestia and Luna were devastated with their failures so they abdicated the throne and let Accord lead instead. But how does Accord turn into Discord and why? That question will be answered soon.