Any of the game's nations can be played during any age, regardless of that nation's fate throughout actual history. Each of the 18 civilizations in Rise of Nations has 4 to 8 unique units. Some unique units are based on units that those nations would have, if they were not destroyed in real-life. For example, the Native American nations (the Aztecs, Maya, and Inca) have unique units in the Modern and Information ages which resemble real-world Iberian-South American guerrillas. There are 4 end conditions: capture, territorial superiority, wonder victory, or score victory.
Gameplay focuses heavily on creating a balance between offense, defense, and economy. Generalship is also needed in this game like most RTS games; this includes a knowledge of the troops and what they are good at fighting. For example, pikemen are better than cannon at killing cavalry. Terrain plays a major part in this game and knowing the terrain is an important asset in battle. Generals can also be created from a fort to aid an army.
Five tactical formations are also available, including the ability to compress or expand the line of battle. When a formation is chosen, the selected units automatically reposition themselves accordingly, typically with faster moving units in the front and slower moving, vulnerable units in the rear.
In a manner similar to chess, slight strategic mistakes early in the game can turn into major tactical problems later on. For example, if a player starts with the nomad setting where no city is built at the start, it is wise to scout for an area that has resources before building a city, for without resources there is no army and the player will lose.
A single-player campaign, Conquer the World, is included in the game. It is comparable to the board game Risk, except that attacks are resolved with a real-time battle, which can last as long as 90 minutes depending upon the scenario. The player can also purchase reinforcements or bonus cards and engage in diplomacy with other nations. Bonus cards and reinforcement cards must be deployed from the Map screen. If the Player attacks a Nation's capital from the Map screen and wins, all of the territory belonging to that Nation come under the control of the Player and that Nation is eliminated. The campaign starts at the Ancient Age and progresses slowly over the course over the campaign to end at the Information Age (present day). During a battle it may be possible to advance to the next available age and upgrade units for the battle.
Rise of Nations uses an Elo rating system to rank players.
Units
There are more than 100 different units in Rise of Nations, ranging from the Ancient Age Hoplite to the Information Age Stealth Bomber. Military units are created at certain structures: the Barracks, Stable/Auto Plant, Siege Factory/Factory, Dock/Shipyard/Anchorage, Airbase, Missile silo, and Fort/Castle/Fortress/Redoubt.
Most Infantry units operate in squads of three, and when a player builds an infantry unit, three soldiers are produced, rather than just one soldier. Exceptions to this rule are: Scout and Special Forces units, armed civilians, flamethrowers, and machine gunners.
Unit types, such as Light Infantry, Heavy Infantry, and Ranged Cavalry, can be upgraded as the player advances through the ages. These upgrades usually represent revolutionary changes in their particular field. For example, the Arquebusier of the Gunpowder Age becomes the Musketeer of the Enlightenment Age, representing the great advantage of flintlock muskets over the earlier matchlock muskets and showing increased attack power and reload speed. Also, each nation gets its own set of unique units. For example, the Greeks can build Companion cavalry; the Russians can build Red Guards infantry and T-80 tanks; the British can build Longbowmen, Highlanders, and Avro Lancaster Bombers; and the Germans get the Tiger and Leopard tanks. In the Thrones and Patriots expansion pack, the Americans can build various Marine units.
Because of the wide variety of units in the game, players have the opportunity to create an army customized to their tastes. Most units have a cost that is roughly equal to that of their peers. Additionally, most units use only two resource types, making the creation of diverse armies easier and almost required. Terraced costs further contribute to the incentive for a diverse army, as each additional unit a player creates of a single type will cost slightly more than the last.
Wonders
Wonders are important buildings in the game. They are real-life structures ranging from the Colossus and the Pyramids to the Supercollider and Space Program. They provide various benefits such as improving resource gathering or making units cheaper. Building wonders can also allow a player to win the game if 'wonder victory' is chosen as a custom setting of the game, as each wonder is worth a preset amount of "Wonder Points". Wonders can be built starting in the Classical Age. The only exception is the Egyptians, who can make wonders an age earlier. As you progress in the game the wonders become more expensive, but generate more points. For example, the Supercollider is worth eight times as much as the Pyramids in terms of Wonder Points.
