Horses are figures too - 4 (with W.I.P)

N.B. Picture updated with a larger and sharper one.

I use the same technique to draw horses, that I use to draw homo sapiens. Namely, the head height as unit for measurement. Served me well in this acrylic study as well -

28" x 22", acrylic on paper.

And here is the W.I.P sequence:

1. The drawing in charcoal - just a basic shape outline with some suggested value changes
2. The drawing lines 'inked' over with burnt umber (mainly) and prussian blue.
3. Added the background (imaginary).
4. Painted a transparent layer (leaving a few areas paper-white), to understand the tonal variations.
5. Opaque layer partly added
6. The finished painting as above. 

Ref image by Breathless-dk in DA.