I very rarely build any cavalry. When I do have it for a battle, I tend to use them either for surgical strikes (run in, hit some archers, drop back, repeat), as scouts, or to take out arty.

My armies are generally 11-12 foot units (balance depends on what I'm going against, and whether I'm defending or attacking) and the remainder archers/arbs and my general. If I bring cav, it's usually just one or two units, and I almost never use them on defense.

I've found that a very effective defensive tactic is to find a hill and make a half-ellipse with spear and hth units (chivalric sergeants/maa work best). Keep one or two hth units in the rear, along with your general, and string missile units out in single-person rows.



Often, the enemy will just be stupid and sit around eating arrows (like the AI can't seem to figure out where to hit the line). It works even better if you're right up against the back of the map, because then when you withdraw spent missile units, replacements come in quickly. The goalie unit is there to go out and hit anything that tries to get around your flank (which doesn't often happen). Just send them out until said attacking unit runs away, then pull them back in.

Sometimes, a horse archer unit or similar can manage to work in behind the enemy and fire with impunity. Stupid AI.