Battle Types
There are two types of battle in Castle Age: dueling and invading. The dueling method is a good system for battle if you have a small army and high personal statistics. Invasions require a large army and powerful equipment. Use your strongest general when you log out of the game since your active general will be in charge of the invasion. Invasions utilize your entire army and each unit will go into battle with a spell to use against your enemies.
Defense
It is good to have a large and well equipped army but it is not enough. You'll also need to increase your defense skills. Log out of the game and log back in if your health score is under ten. You will be safe from opponents when you're logged out and your health will restore.
Spying
You can spy on your opponents by looking at their profiles and examining their equipment. You'll be able to see the land they own and what weapons they have in their possession. Your opponent will be notified you spied on them. This can cause them to attack you.
Army Size
You are allowed a maximum of 501 army units to take with you into battle for an invasion. It is important to remember you can have a larger amount of troops in your ranks, however. Build your army as large as you can so that no matter what you lose in battle, you have another wave of soldiers waiting to invade.