Empire at War 2: Conquest of the Lost Kingdoms is a real-time strategy game with elements of defense, in which you will take command of an urban center that will be attacked by enemies. You will have to start with a small urban center, and as you expand you will be able to construct buildings and improve your defense. 

The enemy will try to attack your urban center, and if they manage to destroy it, they will advance towards your defenses. As you expand, you will be able to build new buildings, new troops, new divisions, and new armies. You will have to use them to protect your defenses and attack the enemy. You will have different types of troops and divisions, such as infantry, archers, and cavalry. Each one has its own characteristics and abilities, and they will play an important role in your strategy. 

You will have an option to construct new buildings and improve your defenses, or you can build new troops, divisions, and armies.