If we're talking about animation errors, Stone of Cold Fire has more animation errors than the rest of the movies combined. I've tried to count them but simply can't, because every time i try i notice a new one.
It seems like grandpa longneck's snout is colored like grandma's more often than it isn't, Littlefoot is off-model for almost the entire film, during the nighttime scene Pterano's head is not the right color (not sure if it's an error or not but it looks pretty bad so i'm counting it as a bad design decision if nothing else), Ducky is off-model rather frequently (and severely, I might grab some examples when I have time), and some small things here and there that are hard to notice.
I think about this a lot because even though 7 is one of my favorites, it suffers from bad art syndrome pretty severely. I have a theory that the movie was animated by Wang's B team while the A team was gearing up to switch to digital inking and painting for the rest of the movies (Big Freeze onwards). No evidence to back this up of course, but it would explain the shoddy animation and constant errors.
