Shogun has one of the few AI's that will actually play under the FOW, even though, of course, it has to know where every unit on the battlefield is or there's no game.

I remember the first time I found this out in a Hojo camp where I had set a trap for an archer-heavy Uesugi army that had invaded Hitachi. I had all of my cavalry secluded in a big patch of woods to the side of the direct approach to my Daimyo. I watched the YS march by followed by all those archers. I kept expecting the spearmen to turn at any second into the woods and decimate my waiting cavalry......but they never did When my own infantry had tied up the Uesugi infantry, my cav burst upon all those helpless archer units from the rear, and the rout was on.

Learning how to conserve ammo will become a very useful skill when fighting multi-stack battles against several thousand enemy troops. Beware of one of the AI's favorite tactics.......using depleted units (in particular Cavalry Archers) to draw arrow fire. Do not, repeat....do not waste your ammo on units like this. Chase them off or kill them with cavalry.

You will run out of arrows eventually anyway, but conserve them as long as possible. If the battle is large enough, and the AI is persistent enough, even teppo can be run out of ammo......although this doesn't happen very often.