The cartoons of that era used multiple layers of painted glass slides to create a full scene, with the background being literally in the back. With each frame the film camera would take a picture of the scene and then the cartoonists would switch out the top pane of glass for the next frame. As someone else said, this whole setup had studio lighting on the drawn scene, but it was difficult to get the colors to match perfectly since they were in slightly different positions and different layers of glass.
Ugh....I know raked joints are a stylistic choice, and in certain cases it looks great, but with the slope on that wall that's just a goddamn water trap, knock years if not decades of longevity off that section of wall....smfh
To make sure there is a secret hidden you need to gently stab that wall with your sword. If it makes a high ringing noise, place a bomb, run away and profit!
This really bothers me. Why would you do all that wall but leave this one section? Roots? You could at least build the new wall in front of it if you have to leave the old stones.
My assumption is they repaired a damaged section of the wall but the material used on the wall originally was not available so they made due with the materials they could find.
It looks really close to that tree. They want to tree to grow, so they make the wall more malleable in that section. If they did the regular wall all the way across, it would look horrible, and probably cause problems for a larger section of wall, when the tree roots start breaking it up on 10 years.
Or else they did do the wall all the way many years ago, but the tree already started breaking it, so they cut out that section.