Horses are an excellent idea as land based transport and as for what was mentioned earlier for combat, mounted troops should gain big advantages over normal foot soldiers (not pikemen or similar) but only when the horse is combat trained. Whoever heard of a carthorse that would be willing to charge into the hart of the battle. This would mean 2 skills for the horse, basic domestication and combat training, obviously a horse that doesn\'t run away at the first sign of combat would cost a lot more than a newly domesticated untrained horse.
As for the use of horses, well flying creatures wouldn\'t be mush good in the labyrinths so a horse would have the graeter flexibility of where it can go in the world whereas flying creatures would have the greater advantage in Yliakum.
