Any units on the ramparts or a tower may charge any enemies they can see in the courtyard. Work out the charges as you would in a normal Warhammer game, remember though that moving from the ramparts to the courtyard costs a unit half its movement. Measure the distance of the movement from the base of the wall. The charging unit may assume any formation it wishes, as long as it fits into the courtyard. If the charged unit elects to flee, they move 2D6" away from the chargers as normal, and the charging unit is placed in the courtyard as if it had moved there normally (see above).