How would you mechanically represent a firefight where one side was defending a train on a monorail and the other side was ambushing it?
I am assuming that in this case the ambushing side is not going to blow up the tracks. I am also assuming that the objective of the attackers is to stop the train without destroying its cargo.
The objective of the train is to make it past the ambush site. Would the train defenders have to achieve enough advances to reach the other side of the battle space?