Here's a running horse from the Buddha documentary we're working on.
Doug Compton did the animation, Christina Riley did all the assistant work -inbetweening and clean up.
There's another cel level. The ground line is animating, it's a beach. And the waves crest and roll back.
The gallop is an eight drawing cycle. The camera then moves around the horse and we're straight ahead on twos until the end of the shot.