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Barding, Medium-Size Creature and Large Creature
Barding is simply some type of armor covering the head, neck, chest, body, and possibly legs of a horse. Heavier types provide better protection at the expense of lower speed. Barding comes in most of the types found on Table: Armor. As with any nonhumanoid Large creature, a horse's armor costs four times what a human's (a humanoid Medium-size creature's) armor costs and also weighs twice as much as the armor found on Table: Armor. (If the barding is for a pony, which is Medium-size, the cost is only double, and the weight is the same.)
Medium or heavy barding slows mounts:
*A mount wearing heavy armor moves at only triple normal rate when running instead of quadruple.
Flying mounts can't fly in medium or heavy barding.
Barded animals require special attention. Care must be taken to prevent chafing and sores caused by the armor. The armor must be removed at night and ideally should not be put on the mount except to prepare for a battle. Removing and fitting barding takes five times as long as the figures given on Table: Donning Armor. Barded animals cannot be used to carry any load other than the rider and normal saddlebags. Because of this, a mounted warrior often leads a second mount for carrying gear and supplies.