Forward Bases

Forward bases are an essential component in assaulting a fortified enemy base. With the larger maps in Age of Empires 2, an army from one's home base will have a long supply line basically eliminating the sending of reinforcements to replace losses. Generally optimal forward bases must be started before the arrival of the castle age. Usually, by then players have walled off the perimeter of their town. Ideally, you want a base in the enemy's backyard where your trebuchets can sit safely destroying the enemy village.

Such a move must occur early to avoid detection. Generally send 2 or 3 villagers escorted by a few men-at-arms to take care of wolves. Your scout should have told you the location of the enemy base. From that location build a barracks or other military building just beyond the view of what you believe to be the perimeter of the base. Wall in the area and plop up towers. In the castle age, add a town center and castle. Start arranging a standing army there to defend if you are discovered and ready to go in when the time is right.

When the imperial age is reached, your base must attack. Crank out trebuchets and hit whatever you can from your base. Kill whatever defenders sortie out and then move out your trebs to go for the kill. Hit the town center(s) and castle(s) first and then all military buildings. After cracking the backbone of a civ, its hard for it to truly recover. Then, set up a supply base there to fuel additional troops to hunt down those who had escaped.

Even if you do not break the resistance of the town, the resulting siege will be beneficial tying down the enemy until you or an ally can deliver the final blow.