I agree, let's find the highest hill we can, with good protection from forests! After that, I think we should go for a plan of deception and defense.
Let's prepare multiple lines of trenches on the hill, and put some 2,000 soldiers in the trenches at the beginning of the battle. The rest should be hidden in the forests. When enough enemies become visible from the hill position, a carefully planned feigned panic act should be played out. Cannons should be turned around and moved up higher on the hill, and some 200 men should run back and forth through the trench systems in a chaotic but pre-arranged manner to make the whole force look even more disorganized and panic-struck. Hopefully this will draw the enemy into attacking the main position. When they do, the infantry in the forests can either strike from the forests, or be sent in to strengthen the trenches, depending on whether the enemy exposes their flank, or the trenches are in desperate need of reinforcement.
Additionally, we should prepare a second bait with our cavalry to make the deception even more convincing. About half of the cavalry could be sent away over very open terrain to make it look like they're on their way to fetch reinforcements, but due to the open terrain, the enemy will believe these reinforcements will be very far away. This, along with the panic playact, will make the enemy think we are weak and our only chance lies in delaying the enemy for long enough to bring reinforcements.
The cavalry commander should have free hands to act depending on the situation. If they are pursued they should of course try to shake off the pursuers as top priority. If they are not, they should wait until the battle has begun at the hill, then return. The cavalry commander should attack either enemy gun positions, infantry or cavalry depending on which enemy forces he considers most isolated and most useful to destroy.
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