Thabit bin Aslam Albanani ثابت بن أسلم البناني · The Book on Jihad

That the Prophet (ﷺ) said: "The best horse is the black one with a spot on the face, and white on the upper lip. Then the one with some white on his lower legs, except for the right. So if it is no black, then the Kumait (red one with black on its ears and its mane) with these markings."