Artist Erik Schumacher didn't paint this striking image of Link atop Epona. It's not a photo either. It's a little bit of both, something called "photomanipulation".
What that means is he took dozens of existing images and smashed them together. Like a collage, only, seamless. Then he joins them all together with trimmings like Link's hat, the Ocarina of Time and the Triforce.
The piece is called "Song of Storms".
You can see more of Schumacher's striking works at his DeviantArt page, linked below.