You and your friends live in vast underground cities, connected to each other by tunnels.
For years your lives have been uncomplicated, and you prospered and advanced. But now, a peril threatens your whole society. Those living above ground have become jealous of your success, and want to end your prosperity.
They are not strong enough to attack your undergound cities yet, but they have a plan to weaken you.
They plan to cut off the commerce between your cities. Mounting huge hydraulic pistons above your underground highways, they force the pistons down and close your roads.
You must stop them, if they cut off your travel, then they can attack each city seperately and defeat you.
