Beast of Burden. The mule is considered to be a Large animal for the purpose of determining its carrying capacity.
Maneuvers. The mule uses maneuvers (maneuver save DC 12). It has 2 stamina dice which are d8s, a dice limit of 1, regains all expended stamina dice when it finishes a long rest, and regains half its total stamina dice when it finishes a short rest. It knows the following maneuvers:
Sure-Footed. The mule has advantage on Strength and Reflex saving throws made against effects that would knock it prone.
Hooves. Melee Weapon Attack: +4 to hit, reach 1 m. Hit: 4 (1d4 + 2) bludgeoning damage.
As an action, you can use the Dash action. If you move at least 4 meters straight toward a creature, you can make a melee weapon attack against it. Add the stamina die to the attack’s damage (add half if you miss by 4 or less).
You can increase the damage for each additional stamina die expended.
As a reaction, which you use when you make an ability check or saving throw to avoid being pushed, knocked prone, or grappled, you can sturdily position yourself. Roll a d3 and add the result to the roll. You can do so after the roll but before any effects of the roll occur.
You can expend 2 additional stamina dice to roll 2d3.
You can expend 4 additional stamina dice to roll 3d3.
As an action, you can use the Dash action. If you use a Brawn check to Overrun a creature during this movement, the creature takes bludgeoning damage equal to the stamina die and is knocked prone.
You can increase the damage for each additional stamina die expended and if you fail to Overrun by 4 or less, the creature takes half as much bludgeoning damage, but isn’t knocked prone.