im sure it was in the patch notes way back when, but your right, it didnt make sense and im not even 100% sure why it was done, but if im not mistaken it was done to all the faction horses? couldnt really tell a difference in the others, tis why the green is so rare but its the most obvious, but i think all faction horse hues were changed back then. not 100% sure on that either tho, and i have no idea which publish that was that changed them