as has been said, cavalry attacks in the rear and their left flank are most effective. try attacking with two or more cavalry units on the same enemy unit. i often get insta-routs from doing this. number of kills vs. cost effectiveness isn't what you should be entirely concerned about it in a cavalry unit. their ability to rout enemy units is their primary role, thus saving your infrantry in losses and ultimately winning the battle. their abilities against unengaged skirmishers and archers are not quite as effective at times, but remember to bring more than one cavalry unit to break these guys. if there is more than one skirmisher/archer you may do great damage to the one unit but the other one rest assured will take from you just as much. thats the role of these guys i find. as cavalry counters they get chewed up but still dish out, but are cheap so easily replaced. unfortunately i found little use for skirmishers/archers beyond their use as cavalry counters. and this really isn't too accurate. skirmishers were the front lines in battles and the only thing they can hit is cavalry and maybe other skirmishers/archers in this mod. the same goes for archers. so far i've never managed to be able to maneuver my archers to the rear in time to hit the enemy in the ass and cause any real damage. i do agree that the effectiveness of these two units in missle attack could be raised a bit so as to reflect their actual use in combat. if this would done, rest assured cavalry flank/rear attacks would be much more difficult instead of almost a certainty which is what they are now. i don't think i've never been able to flank the enemy with cavalry no matter how many cavalry they had.
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