In Rise of Nations you can use waypoints to specify movement paths and to queue attack orders. Similar to the functions of a Rally Point, it controls the behavior of specified units.
Waypoint movement Edit
With a unit or group selected, press Shift, then right-click on the ground to place a waypoint marker. By pressing and holding the button you can also set the direction a formation is facing. The unit/group will proceed from one marker to the next.
Waypoint movement is useful when directing early scouts to certain locations or to specify a movement path around another nation's territory (e.g., when sending a Merchant, Spy or army to a certain location beyond a nation's territory). Furthermore, using this method can allow you sneak behind enemy lines.
Queuing attack orders Edit
With military units selected, you can create an attack queue by right-clicking the targets in the order you want them to be attacked. When a target is destroyed, the units proceed to the next one. This can even be mixed with movement/formation waypoints, e.g. to have an army attack a couple of buildings, then move to another location, facing in a certain direction. This tactic is very useful in eliminating targets with the highest importance or has the greatest threat.
Priority waypoint/command Edit
By pressing Alt + Shift and then right-clicking, a 'priority' waypoint/order is added before all others. For example, if you had given a Scout, who already has a waypoint queue, to deviate from his course to collect a nearby Ruin or to attack a priority target.
Decoy army Edit
You can use waypoint movement and attack queues to create a 'semi-automatic' decoy army: Use the waypoints to send the decoy army around the enemy nation's territory and have them attack some random targets, wait for the enemy to react, then send in your main forces from the other side.
Waypoints can also be used to construct and repair buildings in a specified order. Furthermore, this can ensure that citizens are given a task instead of being idle for a time and you do not have to constantly order a new assignment to a particular worker.
Waypoints can be cancelled by issuing the Halt command (default 'H'), or by issuing any order without holding Shift.