Your army Compositions and tactics.

[Ymarsakar]

The most effective way to retreat my troops that I found was to first send in reinforcements to tie up the enemy my unit is fighting. Then withdraw the unit by making it run away from the enemy front. Because the enemy is now busy fighting my new fresh troops scattered about, there is less blows hitting the troops now retreating. One of the benefits of having troops scattered about a wide frontage.

As for blitzing enemies, I have found that if you send reinforcements of about 4 units to battle an exhausted enemy that has already taken around 50% casualties, they will automatically break due to the change in battle odds. This is different than if you had sent those 4 in earlier, since disciplined units can regain lost morale at a rate high enough that they can avoid breaking for some time, unless you inflict massive casualties on them in a short time.

The easier way to do it is to use many naked fanatics, since their fear ability is just too much for militia and low morale/experienced units to handle.

I've noticed that if I don't pay attention to which unit I am attacking or surrounding, my battles tend to take a lot longer than if I had located the unit that has taken casualties and has wavering or shaken and use my cavalry against them. Even if you just use fresh troops and make them run up and into that unit's line, they can still break from the number of hits your new unit does on them.

The reason why is because normally when you send an infantry unit to attack, they slowly approach the enemy's line once they made contact. If you force them to run into the enemy and past him, your unit will stay in formation and "bunch up" against the enemy. When you then order them to attack, many many more of your unit is now attacking and in contact with the enemy. Statistically this means a faster kill rate, and thus a faster loss of morale.

My solution to the AI running around is to use strategic offense and tactical defense. I attack on the strat map and go into enemy territory, then allow the enemy to attack me. Thus the enemy always comes to me on the battle map, if I can manage it.

Also the solution of using skirmishers and slingers works amazingly well for luring enemy ai units into combat. Once in combat, the enemy AI tends to try to reinforce his units, even if the AI is on the defensive. I once used an entire army of nothing but unarmored horse archers and slingers to destroy a Central European AI spawned army.