When ruling an empire, it's not all about the praise of your people (though that is a pretty good perk). An emperor must defend his people as well as know when it is time to take the battle to the enemy. But be aware, your godlike muscles or killer smile will not be enough to slay the Dark Alliance, rather you must outsmart your enemy, and understand how to strike when most effective.
In Empires and Allies battles, there are a few important things you must pay attention to in order to achieve victory and reap the spoils of battle.
1. First, know your enemy. When you take on a campaign, you will know what units your enemy is attacking you with. When you look at their units, you'll notice there is a yellow bar above their head. That yellow bar is their health, and you can gauge how difficult it will be to take them down based on their health.
2. Next, look at the icon next to the yellow bars above their heads. This icon indicates what type of unit it is, which is important when choosing your own units. When you mouse over the unit you are choosing, it will show three icons that unit is "great against". You want to pick units that are strong against your enemy's units so that you can achieve a swift victory. You can also mouse over enemy units to make sure that you don't choose anything that is weak against them.
If you follow those two steps during empires and allies battles, victory is not far off. In battle, you attack in volleys using one unit at a time. Make your first strike matter by attacking something that is weak against your units. Try your best to keep the upper hand, and make sure you watch your own health bars as well as your enemies. Now you are ready for victory, go forth and take hold of glory!