Tactics using Heavy Cavalry Archers is expensive as these units can take out enemy units in mass numbers, not in solitude. After training a dozen of these, they can be used to take out infantry effectively. The player must make sure they are some feet away from infantry. This tactic does not usually work against cavalry, unless the cavalry can be killed in three or less volleys and should never be employed if the target is in mass numbers (although it can be used against several infantry). Skirmishers and Onagers are devastating against Cavalry Archers, so unless there is no other option they should not be used against those units. Camels also tackle Heavy Cavalry Archers pretty well.