Troops in the courtyard may charge enemies on the ramparts or in a tower as long as they can see them and can move into base contact.

Work out the charges as you would in a normal game of Warhammer. If the enemies on the wall or tower are unengaged they may claim the defended obstacle bonus (attackers need 6s to hit) as they are defending the doors of the towers or stairs up to the ramparts. In the case of towers, up to two models per side may fight across a door. If the enemy models are already engaged, then the chargers may attack them normally. Place the models on the flank of the troops they wish to attack.

Note that you may not charge troops on walls if there is not enough room for them to move into. The walls are already far too crammed with fighting men.