Increases the mounted speed by 20% for all party members within 30 yards. Players may only have one Aura on them per Paladin at any one time. This does not stack with other movement speed increasing effects.
Mount speed modifiers increase multiplicatively, with each modifier increasing the players mounted speed (which is "100% + Mount Speed") by "100% + Modifier". Non-stacking multipliers are the only exception to this formula, in which case the largest possible modifier is only applied (either the product of the stacking modifiers or the non-stacking modifier itself).
The new mount speed achieved with the Crusader Aura can be found through the formula "(100% + Mount Speed) * 120%".