Right, if there's no wall at all, I tend to build a palisade, but only if it's near an enemy. To add to my earlier post. I tend to defend the square rather than go on the walls. For one, my units can never rout, and by then, my towers would've killed about 10% of the enemy already. They also tend to go in one direction, meaning if one unit routs, there is a high possibility of a chain rout.
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