Thats it. You need to put a weapon into a persons weapon slot and then right-click on that weapon to use it. The people have to be able to "reach" the target so if a target is on the left hand side - only the left-front person can hit them. The left-back person must have a ranged weapon or use magic to do any damage. If there is one beast attacking, it usually stands in the middle so that both left and right people can hit him - considerate isn't he
