As it turns out, Shovel Knight is actually a 3D game. More precisely, they're 2D games built in a 3D engine.
This discovery is thanks to the YouTuber Shesez, who recently did an episode on his YouTube channel Boundary Break in collaboration with a Yacht Club Games developer.
Shovel Knight 3D
As reported earlier by Kotaku, David D'Angelo of the studio behind Shovel Knight confirmed in the video that they made the game in a 3D engine because they didn't know exactly what they were making in the beginning.
The programmer explained that the studio knew it probably would've made a 2D game back then, but despite that, it went with 3D just to "cover all the bases." This way, they also had more options to work with, not to mention that it makes things easier when it comes to debugging and bringing the game to a variety of consoles.
That said, as Polygon points out, this allowed the developers to launch Shovel Knight across almost every platform, including on the PC, Nintendo 3DS, Wii U, Switch, Xbox One (no support for the Xbox 360, though), PlayStation 3, PlayStation 4, and PlayStation Vita.
Also, Shesez explains that the studio was supportive and even provided the camera tool used in the video to show the various aspects of Shovel Knight more closely.
After The Initial Shock
Beyond Shovel Knight being a 3D game, the video also had other points worth checking out. It also showed what seems to be leftover assets, particularly some "TB tiles" in the air that look out of place, which D'Angelo described as a "total accident."
Of course, that's just one of the many other bits in the clip.
With all said and done, don't forget to hit up the video below and see what's up. The "3Dness" is shown starting around the 43-second mark, while the explanation from Yacht Club Games begins at about the 1:53 mark.