As johnmcd points out, high casualties are part of good, nutritional breakfast...I mean a good, victorious bridge battle.

Some things that may help your situation:

1) If the enemy starts some distance behind the bridge and you have cavalry, charge them across and try to have then end run the enemy. Either he'll become obsessed with that unit and you'll have to micromanage them (but you'll be able to move across the bridge with less casualties), or he'll ignore them. If the latter, move just just out of his range and let them catch their breath. Begin a cross and if the enemy general becomes exposed, attack him. With luck, he'll panic, making a chunk of his men move off front line bridge defense.

2) If the enemy has archers, you can use either your archers or (better yet) a group or two of ashigaru (in a wide formation) to move up and start to absorb the arrows. Then you can try to assault the bridge proper with your shock troops.

3) Try to have archers on your side move up to the bank close enough to hit either his bridge defense unit (especially if they're weak when it comes to such) or the archer units shooting back at you.

4) If he has little to no archers, send a group of your men halfway across the bridge (or as close as you need to attack his defenders) and then pull them back slowly, allowing your archers to take down the enemy that try to chase them.

5) Always keep an eye on enemy movement. Lines that either break, move, or fall back should be exploited if possible.

As you've found out, bridge battles are nasty affairs. Establishing yourself on the far back is a major key, so you need to weaken both the group defending the bridge and (if possible) their ranged support. Otherwise you'll keep getting the same vicious cycle of men crossing, engaging the spearmen on the other side, getting peppered by arrows, then running.

If possible, assassinate the taisho of the bridge defenders during the same round. You could always use the extra potential of his men running instead of yours.

[This message has been edited by Ii Naomasa (edited 01-08-2001).]